Creating this delicious Keto Broccoli and Cauliflower Au Gratin with Sausage is straightforward if you follow these steps:

1. Preheat Oven: Preheat your oven to 375°F (190°C).
2. Cook the Sausage: In a large skillet, heat olive oil over medium heat. Add the sausage and cook until browned and fully cooked. Break it up into small pieces as it cooks. Set aside.
3. Prepare the Vegetables: In the same skillet, add the broccoli and cauliflower florets. Sauté for about 5 minutes until slightly tender. Remove from heat.
4. Make the Cheese Sauce: In a medium bowl, combine the heavy cream, garlic powder, onion powder, salt, and pepper. Stir in the cheddar cheese and half of the Parmesan cheese.
5. Combine Ingredients: In a large mixing bowl, combine the sautéed vegetables, cooked sausage, and cheese sauce. Mix until everything is well coated.
6. Transfer to Casserole Dish: Pour the mixture into a greased 9×13-inch casserole dish, spreading it evenly.
7. Top with Remaining Cheese: Sprinkle the remaining Parmesan cheese on top of the mixture for a delicious golden crust.
8. Bake: Place the casserole in the preheated oven and bake for 30-35 minutes or until bubbly and golden on top.
9. Garnish and Serve: Remove from the oven and let it cool slightly. Garnish with fresh parsley if desired.

By following these steps, you’ll create a mouthwatering dish that’s perfect for any occasion!