Step 1: Prepare Your Ingredients

Preheat your oven to 350°F (175°C) and generously grease a 9×13-inch baking dish with olive oil or cooking spray. Brown the gluten-free breakfast sausage in a large skillet over medium heat, breaking it into small pieces as it cooks, about 5-7 minutes. Once fully cooked, transfer to a paper towel-lined plate to drain excess fat.

Step 2: Sauté The Vegetables

In the same skillet, add a small amount of oil if needed, then add the diced onions and bell peppers. Sauté until the vegetables begin to soften, about 4 minutes. Add the chopped spinach and cook just until wilted, approximately 1 minute. Remove from heat and allow the mixture to cool slightly.

Step 3: Create The Egg Mixture

In a large bowl, whisk the eggs until well blended and slightly frothy. Pour in the milk while continuing to whisk. Add the garlic powder, dried oregano, salt, black pepper, and paprika, mixing until thoroughly combined. This well-seasoned egg mixture forms the foundation of your Gluten Free Breakfast Casserole.

Step 4: Assemble The Casserole

Spread the cooked sausage evenly across the bottom of your prepared baking dish. Layer the sautéed vegetable mixture on top of the sausage. Sprinkle 1½ cups of the shredded cheese evenly over the vegetables, reserving ½ cup for later. Pour the egg mixture carefully over all the ingredients, ensuring everything is evenly covered.

Step 5: Bake To Perfection

Sprinkle the remaining ½ cup of cheese and the sliced green onions on top of the casserole. Bake uncovered in your preheated oven for 35-45 minutes, or until the center is set and no longer jiggles when gently shaken. The top should be beautifully golden brown with slightly crisp edges. Allow your Gluten Free Breakfast Casserole to rest for 5-10 minutes before garnishing with fresh parsley and slicing.