Combine the ground beef, cauliflower, onion, tomato paste, salt, and pepper. Divide between the peppers.
Bake for 45 minutes or until the filling is cooked and the peppers have softened.
Top with the marinara sauce and serve.
Nutrition: each stuffed pepper half has 4.3 NET carbs.Substitutions: exchange the ground beef for ground turkey, chicken, or sausage.Prep Time: you can prep the peppers ahead of time and stuff them. Place them in the fridge overnight and bake the next day. To Reheat: warm them in the microwave, covered for 1-2 minutes or until hot. You can also heat them in the oven at 350 degrees for 10-12 minutes or until hot. Another way is to heat them in an air fryer at 375 for 6 - 8 minutes. To Freeze: wrap each of the peppers with plastic wrap, then keep in a freezer-safe container. They need to be totally thawed before reheating, so place them in the fridge overnight so they can defrost.