Slow Cooker Low Carb Keto French Onion Chicken Soup

This cozy keto French Onion Chicken soup has 30 grams of protein per serving. It’s a comforting, satisfying and easy recipe for the slow cooker or stove top. 

French Onion Slow Cooker Chicken Soup (Keto, High Protein & Cozy)

I originally tested this French Onion Slow Cooker Chicken Soup on New Year’s Eve with friends.

It was one of those nights where you want something warm, comforting, and special — but still aligned with how you eat. Everyone loved it. Bowls were scraped clean.

Now it’s February and it’s become a family favorite and been on repeat. While New Year’s Eve is behind us, winter absolutely is not. Cozy soups are still very much in season.

In fact, this is the time of year when we crave warm, rich meals the most, don’t you think?

This recipe takes everything we love about classic French onion soup — the sweet caramelized onions, the deep flavor, the melted cheese — and turns it into a high-protein, low carb, keto French onion chicken recipe that actually satisfies.

And that protein piece? That matters more than ever in midlife.

Why This Is the Best Keto French Onion Chicken Soup for Midlife

Traditional French onion soup is mostly bread, cheese, and broth. Delicious? Yes. Satisfying long term? Not always.

This version swaps in:

• chicken breasts
• yellow onions
• Rich chicken broth
• Creamy, nutty Gruyere cheese
• Fresh thyme and a quick keto bread on top, optional of course

You still get that deep golden brown, caramelized onion flavor. But instead of relying on bread for bulk, we prioritize tender chicken.

The result is an easy French onion chicken soup with:

• Higher protein
• Moderate fat
• Lower net carbs
• Long-lasting satiety

That’s what makes this one of my favorite low carb recipes for winter.

Why Protein Is So Important in Midlife

Let’s talk about something that doesn’t get enough attention: protein and satiety.

As we move through perimenopause and menopause, muscle loss naturally accelerates. If we’re not intentionally prioritizing protein, we lose lean mass. And when we lose muscle, metabolism slows, bones get weaker, and we can’t bounce back from injury as we did when we were younger.

Protein does several powerful things:

• Helps preserve muscle
• Supports blood sugar stability
• Increases satiety
• Reduces cravings later in the day
• Helps prevent overeating

When you eat a bowl of traditional French onion soup, it may taste comforting, but it’s often lacking protein. That can lead to feeling hungry again quickly.

This keto French onion chicken recipe gives you the same comfort — but because it’s built around chicken, it helps you stay full longer.

This fits beautifully into my midlife macro approach:

• High protein
• Moderate fat
• Controlled carbs
• Whole food focused

It’s comfort food with intention.

Serving topping Option 1: 90 second Bread

For New Year’s Eve, I used my 90-second cottage cheese bread.

I made one batch (4 servings) in an 8 by 4 loaf pan and microwaved it for 2.5 minutes, sliced it, then toasted the slices and laid a slice right into each bowl of soup.

Then I:

• Sprinkled extra Gruyere on top
• Ladled hot broth over the bread

That’s it. No broiling.

The bread softens slightly and absorbs that beautiful broth without becoming mushy.

You still get the French onion experience — just with protein-forward bread instead of a carb-heavy baguette.

Serving Topping Option 2: Parmesan Biscotti

Another incredible option!

My savory parmesan biscotti recipe.

These crisp, cheesy slices are perfect for dipping into the soup.

They hold up beautifully in broth and add texture without the heavy carb load of traditional bread.

It feels elegant. Restaurant-worthy. But still aligned with keto, THM recipes, and midlife macros.

Ingredient Swaps & Great Options

You can easily customize this recipe:

Protein Swaps

• Use skinless chicken thighs for more richness.
• Add a splash of Worcestershire sauce.
• Combine chicken broth with a little beef broth for deeper flavor.

Onion Options

• Try white onions or red onions.
• Add a splash of white wine, red wine, or balsamic vinegar while caramelizing.

Fat Options

• Swap olive oil for avocado oil or coconut oil.
• Stir in a little additional butter at the end for extra richness.

Cheese Options

Swiss works beautifully too.

Substitute mozzarella cheese if needed.

Why This Works So Well in Midlife

This soup isn’t just cozy. It’s strategic.

Because it prioritizes protein, it helps:

• Keep you full
• Reduce late-night snacking
• Support muscle retention
• Stabilize blood sugar

Instead of relying on bread and cheese for fullness, we build the base with chicken and caramelized onions.

That’s how you enjoy comfort food without derailing progress.

This is what it looks like when classic comfort food evolves.

Deep flavor. Melted cheese. Sweet onions. Tender chicken.

Still winter. Still cozy.

Just smarter.

Storage & Meal Prep

• Store in an airtight container up to 4 days.
• Freeze in a freezer-safe container up to 3 months.
• Portion into single servings for easy lunches.

Reheat gently over medium heat.

Slow Cooker Low Carb Keto French Onion Chicken Soup