Preheat the oven to 400 degrees F. Grease a round skillet with cooking spray.
In a medium bowl whisk together the eggs, salt, pepper, garlic and onion powder
Over low heat, gently wilt the spinach. This may require a touch of oil on the pan.
Let the spinach slightly cool and add the cheese to the egg mixture.
Reheat the frozen butternut squash according to package directions so that it's not frozen.
Add spinach and butternut squash to egg mixture. Add 2 tbsp. of cheese on top.
Pour mixture into greased skillet and bake for 25 to 30 minutes. You will want to make sure that the center is no longer wet.