Preheat oven to 350 degrees F and prepare a baking dish with non-stick cooking spray and set aside.
Ground and cook sausage in a skillet until fully cooked. Add garlic, peppers, and onions to the skillet and sauté with sausage for 2 minutes. Place this in your prepared baking dish. Add chopped spinach on top.
In a separate bowl whisk eggs with salt and pepper. Pour egg wash over vegetables in a baking dish and gently mix to make sure eggs are covering the entire dish. Top with cheese and bake for 45 minutes or until a fork can come out clean and eggs are cooked all the way though.