Preheat your oven to 375°F. Lightly grease a large baking dish.

Cut the tops off the bell peppers, remove the seeds, and trim any excess membranes. Slice each bell pepper in half and arrange them in the prepared baking dish.

In a large non-stick pan, heat olive oil over medium heat. Add the chopped onion and sauté for about one minute. Add the ground beef and cook until it is no longer pink. Stir in the taco seasoning, then pour in the diced tomatoes with their juices. Let the mixture simmer for 1 minute.

Remove the pan from heat and mix in the steamed cauliflower rice and one cup of shredded cheese.

Divide the beef mixture evenly among the bell pepper halves and sprinkle the remaining cheese on top.

Bake the stuffed peppers for 20-25 minutes, until the cheese is melted and the bell peppers are tender.

Take the stuffed peppers out of the oven and serve immediately.