This Keto Mexican Beef and Cauliflower Casserole is a flavorful low-carb dish perfect for those following a ketogenic lifestyle. Ground beef is cooked with taco seasoning, onions, and bell peppers, then layered over tender steamed cauliflower and topped with sour cream and melted cheddar cheese, resulting in a comforting, cheesy casserole full of authentic Mexican-inspired flavors.