Creating this delicious Keto Taco Casserole is a breeze when you follow these simple steps:

1. Preheat the Oven: Preheat your oven to 350°F (175°C).
2. Cook the Meat: In a large skillet over medium heat, brown the ground beef until fully cooked. Drain excess fat if necessary.
3. Add Vegetables: Stir in the chopped onion, bell pepper, and minced garlic. Cook until the vegetables are tender, about 5 minutes.
4. Season: Add the diced tomatoes (with juices) and taco seasoning to the skillet. Mix well and let it simmer for 5 minutes.
5. Incorporate Cauliflower Rice: Add the cauliflower rice to the mixture, stirring until everything is well combined. Season with salt and pepper to taste.
6. Layer Casserole: In a greased 9×13-inch baking dish, spread half of the meat mixture evenly across the bottom.
7. Add Sour Cream: Spoon half of the sour cream over the meat mixture, spreading it evenly.
8. Repeat Layers: Add the remaining meat mixture on top of the sour cream, followed by the rest of the sour cream.
9. Top with Cheese: Sprinkle the shredded cheddar cheese generously over the top.
10. Bake: Place the casserole in the preheated oven and bake for 25-30 minutes, or until the cheese is bubbly and golden.
11. Garnish: Remove the casserole from the oven and let it cool slightly. Top with shredded lettuce, avocado slices, and chopped cilantro before serving.

These straightforward steps will guide you in making an incredible Keto Taco Casserole that your whole family will love!