These absolutely delicious Keto 3-Cheese Mini Quiches are LOADED with cheese (three different kinds!) and flavorful vegetables. Serve for breakfast, lunch, dinner, or a snack.
Preheat oven to 350 F and spray a muffin pan with non-stick cooking spray.
Add olive oil to a medium skillet over medium-high heat, then add chopped onion and chopped pepper. Stir occasionally until the vegetables are soft, about 5-6 minutes.
Add the thawed and drained spinach (I usually hold the spinach in my hand and give it a good squeeze to drain it) and cook until the mixture is no longer moist.
Add eggs, shredded mozzarella and cheddar cheeses, salt, and pepper to a large bowl. Mix to combine, then add the vegetable mixture and mix to combine again.
Pour egg mixture into a muffin pan. Top each muffin with 1 tsp shredded Parmesan cheese.
Place muffin pan in the oven and cook for 25-30 minutes until eggs have cooked and the muffins are lightly browned on top.