Prepare Oven and Dish: Set your oven to preheat at 365°F (185°C). Lightly grease your medium casserole dish with cooking spray or a little extra olive oil.

Brown the Sausage: Add 1.5 tsp of olive oil to the large skillet over medium-high heat. Remove the sausage from its casing (if necessary) and add it to the hot skillet. Cook, breaking the sausage apart with a spoon or spatula, until it's fully cooked and lightly browned, about 5-7 minutes. Add the pinch of red pepper flakes (if using) during the last minute of cooking. Drain off any excess fat and spread the cooked sausage evenly over the bottom of the prepared casserole dish.

Sauté the Mushrooms: If needed, wipe the skillet clean. Add the remaining 1.5 tsp of olive oil and heat over medium-high. Add the sliced mushrooms and cook, stirring occasionally, until they release their moisture and it evaporates, and the mushrooms begin to brown slightly, about 6-8 minutes. Distribute the cooked mushrooms evenly over the sausage layer in the casserole dish.

Add First Cheese & Onion Layer: Sprinkle half of the shredded Mozzarella (3/4 cup) and all of the sliced green onions over the mushrooms and sausage.

Prepare Egg Mixture: While the sausage and mushrooms are cooking, place the cottage cheese in the fine mesh strainer. Gently rinse it under cold water and allow it to drain very well, pressing lightly to remove excess moisture. In the medium mixing bowl, whisk the 8 large eggs until the yolks and whites are thoroughly combined. Stir in the drained cottage cheese, grated Parmesan cheese, Spike Seasoning, garlic powder, and black pepper to taste.

Combine and Top: Pour the prepared egg mixture evenly over the ingredients in the casserole dish. Use a fork to gently poke and slightly mix the ingredients, ensuring the egg mixture coats everything without excessively disturbing the layers.

Final Cheese Layer: Sprinkle the remaining half of the shredded Mozzarella (3/4 cup) evenly over the top.

Bake the Casserole: Place the casserole dish in the preheated oven. Bake for 35-40 minutes, or until the center is firm to the touch (no longer jiggly) and the top is golden brown.

Rest and Serve: Let the casserole rest for 5-10 minutes before slicing and serving. This helps it hold its shape better.