Preheat the oven to 350 F.
Melt some cooking fat in a skillet over medium heat, and cook the onion and garlic until fragrant.
½ cup yellow onion, Cooking fat, 2 garlic cloves
Add the bell pepper and mushrooms and cook until soft, 2 to 3 minutes.
½ cup bell pepper, ½ cup mushroom
Add the spinach, season everything to taste, and cook for another minute and set aside.
1 cup spinach, Sea salt and freshly ground black pepper
In a bowl, whisk the whole eggs and the white eggs, and season with salt and pepper.
4 whole eggs, 4 egg whites, Sea salt and freshly ground black pepper
Fill each muffin tin with a layer of cooked vegetables, then top with beaten egg mixture.
Tiny muffin pan
Place in the oven and bake for 15 to 18 minutes or until the eggs are set.
Serve the egg muffins topped with chives and freshly diced tomatoes.
2 tbsp. fresh chives, 1 small tomato