Oven Prep: Set the oven’s temperature to 200°C (390°F).
Blanch the cauliflower by heating up a big pot of water and adding a tablespoon of salt. After blanching for around five minutes, the cauliflower florets should be somewhat soft but still crisp. After draining, put away.
Cook the meat and vegetables:

Heat Oil: Place the vegetable and olive oils in a big pan and heat them over medium heat. Add the minced garlic and chopped onion, and sauté until the onions are transparent.
Prepare the Vegetables: To the skillet, add the chopped carrot, green pepper, and red bell pepper. Cook until the veggies begin to soften, another five to seven minutes.
Add Minced Meat: Transfer the minced meat to the skillet and turn the heat up to medium-high. Using a spoon, break up the meat and heat it until it’s browned and well cooked.

Season: Add the tomato sauce to the beef mixture after seasoning it with paprika and black pepper. Simmer for a further two minutes to blend the flavors. Take off the heat.
Put the Casserole Together:

Layer Cauliflower: Arrange the blanched cauliflower as the bottom layer in a baking dish. Next, cover the cauliflower with a uniform layer of the meat and vegetable combination.
Add Cheddar: Over the layer of meat, scatter the shredded mozzarella and cheddar cheeses.
Cook:

Bake Casserole: Bake for 20 to 25 minutes, or until the cheese is bubbling and browned, in the preheated oven.
Serve: