Preheat oven to 375 degrees. Spray a 9x13 baking dish with cooking spray.
Place a skillet on medium-high heat. Add the chopped veggies (excluding the spinach) to the pan. Sautee for a few minutes until the veggies are soft.
Add the veggies to the bottom of the baking dish. Spread the veggies throughout the dish.
Add another layer, add the spinach.
Whisk the egg whites and eggs in a small bowl. Season with salt and pepper. Pour the egg mixture over the veggies.
Create an additional layer by adding the crumbled sausage (or bacon) and cheese.
Bake for 35 minutes.
Remove from the oven. Allow to cool before serving. Enjoy!