Place your cauliflower florets in a steamer and steam until just tender, you don't want them too soft.
Cook your bacon in a large skillet until crisp. Remove and set on a paper towel lined plate.
Drain the bacon grease from the skillet and cook the ground beef in the same skillet, once browned add the onion and cook until softened.
Add the florets and keep on low while making the cheddar cheese sauce.
To a medium sized sauce pan, add the butter on low heat to melt.
Whisk the arrowroot powder and milk together in a bowl.
Pour this into the sauce pan and bring to a simmer.
Reduce heat to low and stir constantly until mixture thickens and coats the back of a wooden spoon.
Add the remaining ingredients and stir until cheese is melted.
Serve this over the cauliflower burger mixture.
If you'd like this a little more browned on top, just place it under the broiler for a few minutes.
Top with bacon and enjoy immediately!