Easy Keto Nut Free Low Carb Sugar Free Lemon Mug Cake
This easy keto Sugar Free Lemon Mug Cake is low carb, nut free, gluten free, and a single serving for perfect portion control! Just 3 grams net carbs!
Easy Keto Lemon Mug Cake
There is just something about tangy lemon flavor that feels like hope in dessert form. Bright. Fresh. Clean. Even in the dead of winter here in New England, the smell of lemon instantly reminds me that spring will come again.
This Sugar-Free Lemon Mug Cake is one of those recipes I keep coming back to year after year, (first published in March 2015)—especially when I want a single serving sweet treat without leftovers calling my name from the counter.
It’s also one of the easiest recipes the next time you are craving a lemon dessert!
It’s:
- Low carb and keto diet friendly
- Gluten free, grain free, and nut free
- Made with coconut flour (not almond flour)
- A true single serving with built-in perfect portion control
- Just 3 net carbs per serving
It’s the easiest way to satisfy a sweet tooth without blowing your goals.
Why Lemon Has Always Been My Go-To
I’m a lemon lover—always have been.
Lemon in my water, lemon in my seltzer and in lemon recipes as much as possible.
Sugar-Free Frozen Lemonade, this Strawberry Lemon Sorbet, and these delicious No Bake Lemon Cheesecake bars have been reader favorites for years.
But lemon is also personal for me.
When my throat feels scratchy or sore, I’ve literally taken the juice of an entire lemon as a quick shot. It might sound intense, but it works better for me than anything else I’ve tried. Lemon has always symbolized healing, freshness, and getting back on track—especially during cold, snowy months.
This mug cake was born out of that same mindset: something comforting, simple, and supportive.
The Testing Behind This Recipe
Before this recipe ever went live, I tested it four different times.
- Coconut flour only
- Coconut flour with flaxseed
- One egg vs two eggs
- More lemon juice vs less lemon juice
I was looking for fluffy texture, not rubbery. Moist, not dry. Lemon-forward but not overpowering.
This version is the winner.
Even if you think you don’t like coconut—trust me—the coconut flavor is not noticeable here. The lemon is the star. My youngest, who hates coconut in every form, absolutely loved this.
Sugar-Free Lemon Mug Cake Ingredients
Dry Ingredients
- Coconut flour
- Baking powder
- Pinch of salt
Wet Ingredients
- Egg
- Fresh lemon juice
- Heavy cream (or coconut cream)
- Lemon liquid stevia
Using coconut flour is essential here. Almond flour cannot be swapped evenly—the texture will not work.
Coconut Flour & Allergies: Let’s Clear This Up
I get this question almost daily.
Is coconut a tree nut?
Botanically speaking, coconut is actually a fruit (a drupe, like a peach with a pit). While the FDA classifies coconut as a tree nut for labeling purposes, it is not a botanical nut.
My own son was diagnosed with a peanut and tree nut allergy at age two. He has safely eaten coconut for years without issue.
That said, if you have allergies, always check with your allergist.
The American College of Allergy, Asthma & Immunology explains that while coconut reactions are possible, most people with tree nut allergies tolerate coconut just fine.
Why This Is the Perfect Mug Cake
This is one of those low carb mug cakes that actually works:
- Uses a microwave-safe mug or small ramekin
- No fancy equipment
- No leftover cake sitting on the counter
- Ready in about 1 minute of cooking time
It’s ideal for anyone following a low-carb lifestyle, ketogenic diet, or anyone simply wanting better portion control.
Easy Lemon Mug Cake Frequently Asked Questions
Can I make this dairy free?
Yes. Swap the heavy cream for canned coconut cream.
Can I use a different low-carb sweetener?
Absolutely. Use any low-carb sweetener you prefer. If you need help adjusting amounts, my Sweetener Guide & Conversion Chart makes it easy.
What size ramekin should I use?
A 7-ounce ramekin works best. You can also divide the batter into two smaller ramekins for 2 single servings of this sugar-free mug cake.
Can I bake this instead of microwaving?
Yes.
- Preheat oven to 350°F
- Bake for 10 minutes or until a toothpick comes out clean
What’s the frosting shown in the video?
That’s my sugar-free vanilla buttercream frosting—totally optional but delicious.
Why I Still Love This Recipe Years Later
This recipe may be simple, but it represents everything I believe in now more than ever:
- No all-or-nothing thinking
- No white-knuckling through cravings
- Simple recipes that support long-term health
Sometimes the best dessert is the one that lets you enjoy a few bites and move on—satisfied, not spiraling.
And if you’re someone who loves lemon as much as I do, this one never disappoints.
More Keto Mug Cake Recipes
More Sugar Free Lemon Recipes: Lemon Cheesecake Mousse, Lemon Custard Pie, Crock Pot Lemon Blueberry Cake.
Other Low Carb Recipes You Might Like:
- 1 Minute Sugar Free Chocolate Mug Cake
- Pumpkin Chocolate Chip Mug Cake
- Red Velvet Couples Mug Cake
- Carrot Cake Mug Cake
Need help meal planning? My weekly Midlife Macro Meal Plans are available each week using all my recipes for low-carb meals, and snacks.
If you’re following a classic keto diet, this meal plan works for both low carb, midlife and classic keto approaches, sent directly to your inbox. Easy meals each night of the week! Shopping list is done for you! Want a sample plan?
Sugar-Free Lemon Mug Cake
Ingredients
- 1 egg
- 2 tablespoons lemon juice and lemon zest optional
- 2 tablespoons heavy cream
- 1/2 teaspoon lemon liquid stevia or 1/4 cup low carb granular sweetener
- 2 tbsp coconut flour
- 1/4 teaspoon baking powder
- pinch salt
Instructions
- Whisk the egg, lemon juice, cream and stevia together in a small bowl.
- Stir in the coconut flour, baking powder and salt.
- Pour batter evenly into two 7 ounce ramekins or or 1 microwave-safe mug or bowl.
- Microwave 1 minute then in 30 second intervals for each lemon cake or until toothpick in center comes out clean.
- Top with sugar free whipped cream if desired!
Oven instructions
- Preheat your oven to 350 degrees F. Bake for 10 minutes or until a toothpick in center comes out clean.
Video
Notes
Nutrition
About Brenda
Brenda Bennett is a certified Nutritional Therapy Practitioner, certified Sugar Detox Coach, certified Keto Coach, and certified Life Coach. She has been Sugar Free & refined-carb free for 20 years and is the author of four cookbooks: Sugar-Free Mom, Naturally Keto, The 30-Day Sugar Elimination Diet, and her newest release, Good, Better, Best (2025). Her work focuses on helping women detox from sugar, eliminate cravings, balance blood sugar, and lose weight while enjoying delicious, nutrient-dense whole foods. Brenda is also the creator of the Midlife Macro™ Method and the weekly Midlife Macro Meal Plans™, designed specifically for women in perimenopause and menopause who want simple, high-protein, low-carb meals to support hormones, metabolism, and long-term health.She is the founder of the Sugar Free Fresh Start course and the Sugar Free Mom Tribe membership.
Where is the icing recipe you used in the video?
https://www.sugarfreemom.com/recipes/sugar-free-vanilla-buttercream-frosting/
I’m not allowed any citrus. I want to use your basic mug recipe to do a plain vanilla or chocolate mug cake. Any suggestions please of what I can use to replace the fluid amount of the lemon juice?
maybe just unsweet almond milk
Will you please tell me where you purchase flavored liquid stevia?Our Health Food store has liquid stevia but not the flavored. This recipe looks so very delicious!
I buy all the flavors on Amazon as I found that to be the cheapest.https://amzn.to/2Y0XjVS
This was amazing, the perfect amount of tart to a touch of sweet!! Your recipes don’t disappoint, thank you.
Thank you!
Btw coincidence two Theresa commenters back-to-back… I’m the 2nd one! Just made it again!!!! Thank you again!
A huge and delighted thank you for this LEMON mug cake recipe! After making my family an apple-based dessert yesterday, and actually during a hunt for a cranberry mug variation (thanks I’ve bookmarked that, too), LEMON struck me with a massive craving! Whipped this up, put it in the freezer just long enough to make whipped cream for everyone and…omg! YUM! Going to make another one tonight! LEMON just might be my new chocolate!!!
I wanted to love this! My husband wanted this tonight, well I decided to try it before tonight. I did not like it. It taste of coconut not lemon. And it was not sweet at all, I mean not even a little. I dont crave sweets anymore since on keto but wow this was not at all something I would make again. Sorry.
I made this last night but didn’t work out for me, was very rubbery that could be as I didn’t have any coconut flour or lemon liquid stevia. How can I change to a non gluten free recipe ?
What flour did you use?
Hi there! I agree that the texture of this cake is surprisingly smooth and fluffy, unlike most coconut flour recipes. I used coconut cream instead of HWC. Since I didn’t have lemon stevia, I used plain stevia glycerite with 1/4 tsp lemon extract. I gave the first ramekin to my DH with a few low-sugar chocolate chips on top. He loved it! For mine, I added lemon zest, and it was fantastic! As a lemon zest lover, and a cheapskate, er, frugal wife 🙂 I can’t bear to throw away unzested organic lemon peels, haha! Anyway, thanks for a great recipe! I think I will try it with a raspberry or two next time. 🙂
Thank you!
Hi, I am looking for a great sugar free dessert to make for a friend’s birthday. I think I found it! My question is can I make this ahead of time or does it need to be served immediately after baking?
My experience with mug cakes is tjat they get a litle chewy after they start to cool down.
Thanks
Actually I personally think it tastes even better after being refrigerated overnight. Definitely not chewy you’ll find it very moist.
I just made this and was pleasantly surprised at the texture.
I usually don’t like coconut flour or mug cakes for that matter.
They always seem to be very very dry and with a texture that I don’t like.
I really enjoyed this little cake.
The texture reminds me of shortbread…and I love that.
Thanks for sharing!
Thank you Linda!
I have been following your blog in the past year since completely changing my food habits and lifestyle. In the last year I’ve lost over 120 pounds and am only 8 away from my personal goal. Your blog has given me so much hope and helped me realize that I can live healthy life without feeling like I have to give up “treats” forever. I just made this for myself and OH MY WORD! SOOOOOO amazing! I didn’t use lemon stevia (I don’t have any flavored stevia) and I added 1/2 a tablespoon of skim ricotta. I also made a lemon glaze with 1 tablespoon powdered swerve and 1/2 tablespoon lemon juice. And ate this cake with fresh blackberries and strawberries. With the little bit of ricotta it made it soooo fluffy and almost reminiscent of a cheesecake! Thank you for all you do and for providing recipes that are simple, delicious, and don’t taste like you’re making sacrifices. This has been a hard year for me but your recipes have helped to make it a transformative experience. THANK YOU!
In a few months I’ll be posting a bunch of the recipes that I’ve enjoyed this year on my personal blog and this one will definitely be on the list!
This is wonderful! My OH is a big fan of lemon flavoured desserts, so this is just the ticket when I’m in more of a chocolatey mood 🙂 A lemon mug cake for him, and a chocolate one for me! The only change I made was to use 2 teaspoons of Trivia rather than lemon Stevia, which I didn’t have. I also had to microwave it for much longer, almost 3 1/2 minutes (in 30 second bursts after the first 1 1/2 minute), but that could just be my microwave, or the size of the ramekin I used. Nonetheless, this was delicious topped with a tablespoon of crème fraîche and a few blackberries. Summer in a cup! (Or at least I wish it was!) Thank you so much 🙂
Glad to hear thank you!
Oh my goodness! I have tried so many mug cakes and they usually satisfy (if I make them right) but this goes beyond! It is delicious!! I used swerve instead of stevia because that’s what I bake with, I am taken back by how not only how good it is, but how easy it was! Thank you! I will be pinning and making it again for sure- now all I have to do is try your other recipes, well eventually. This one will be in the top rotation for a while! Lol
So happy you liked it!
Love this delightful recipe. Used a large ramakin, greased. Instead of lemon stevia liquid I used juice and finely grated zest of half a large lemon and teaspoon of granulated erythritol/stevia. Might try lime next time. Served warm with double cream. Yum.
Hi I have to make 200 mini cupcakes, can this be done in little muffin tins?
I think that would work well.
Made it tonight and it’s delicious – I added some Keto cream cheese frosting and it was like a restaurant dessert !!! Thank you for a keeper recipe
Yum!!! I used sour cream instead of cream (I had some in the fridge that needed using up) and used 2tsp of Sugarless stevia organic granules instead of liquid stevia, the cake was really delicious, just what I needed to satisfy my dessert cravings!
Just ran across your recipe & had to make it NOW!!!!! Even at 10:30 pm! Used unsweetened Almond milk vs. the cream. Came out wonderful & with even LESS fat & calories! Topped it with fresh blueberries. YUM!
Your video shows your ramekin is greased but your written recipe does not tell you to grease your dish. Would be nice to add since I tried making mine in a mug and was planning on cooking in the mug but wondered where the oil is. Otherwise, great recipe!
Thanks!
I don`t know which coconut floor you used, but this 2 tablespoon contains 13,9 carbohydrates! I used coconut floor which contains carbohydrates as much as 17 gram in 100 g. 2 tablespoon cannot possibly weight over 100 gram, guess 16-20 gram.
A well in the center after baking.
Hidy from Texas, Brenda!
This is so luscious. I had a little set of creme brule wide and flat (only about an inch high rim) ramekin/crock dealios that hold exactly 8 oz water. I thought they’d be so cute to serve this elegant and lemony cakette. I was askeert they would run over the edge in their rise.
No no no they did not overflow and they are so dang cute not to mention lemon-tasty!
I had to make a well in the center and pour in organic heavy cream. Omgosh! It’s nothing short of lemon heaven!
Thank you so much for sharing and for your innovative creativity. I always enjoy your email selection of recipes. I appreciate your time!
Elaine in Big D
Thank you so much!
Yum! Best mug cake yet, great texture.
Thanks!
My Mom always gave us hot lemonade to sip on when we were sick and/or a sore throat. Always worked.