Cook cauliflower, onion, garlic, and bell pepper in oil for about 10 minutes, then cool.
Combine cauliflower mixture with the ground beef, egg, and cheddar cheese.
Place 1/3 of the beef mixture on each cabbage leaf and roll.
Place rolls seam side down in a baking dish and cover with tomato sauce.
Baked for 1 hour at 350 degrees F.