In a large bowl, crack the eggs and whisk them together with the paprika, garlic powder, salt and pepper. Set aside. Preheat oven to 425 degrees.

In an oven-safe skillet or cast iron pan, heat the oil or bacon grease over medium-high heat. Add the chopped red peppers and sauté for 2-3 minutes, until they begin to soften. Add the mushrooms and sauté another minute. Add the sausage, green onions & spinach and cook just until spinach starts to wilt, about 1 minute.

Reduce the heat to medium-low. Pour the eggs into the skillet over the sautéed vegetables & sausage and cover the skillet with a lid. Cook over medium-low heat, without stirring, until the egg begins to look set around the edges and start to release from the pan but the middle is still wobbly, about 5 minutes.

Transfer the skillet with the frittata to the oven and let it bake for 9-10 minutes until the middle is set. If you are doing meal prep and plan to reheat the frittata later, try to undercook it just a little bit (maybe only 8-9 minutes). Then when you reheat each portion in the microwave it will be perfectly cooked.