Muffin Pan Crustless Kielbasa Quiches

I like to make these on Sunday and then eat them throughout the week for breakfast. They are easily reheated in the microwave. 

olive oil spray
1/2 medium onion, diced
2 garlic cloves, crushed
1 medium tomato, diced
6 oz turkey kielbasa, diced
2 cups baby spinach
5 large whole eggs, beaten
4 large egg whites
1/3 cup fat free milk
1/3 cup all purpose flour
1/2 tsp salt
1/8 tsp black pepper
3 oz shredded cheddar cheese

Preheat oven to 350°F. Spray a nonstick muffin pan with olive oil spray.
Spray a non-stick skillet with olive oil and heat on medium.  Sauté onions until soft, and then add the garlic, tomato, and kielbasa. Sauté for another 5 to 7 minutes. Add spinach and cook until wilted, about 1 minute.  Set aside.

Meanwhile, in a large bowl, whisk the eggs, egg whites, milk, flour, salt and pepper until smooth. Add the cheese and cooked kielbasa mixture to the bowl and mix well. Pour into the prepared muffin pan and bake for 28 to 30 minutes, or until firm. Serving size is two muffin-sized quiches. 
These can be frozen and reheated later.

Recipe modified from Skinnytaste