Heat olive oil in a saucepan over medium heat. Add the diced onion and bell pepper. Sauté until fork-tender, about 5 minutes.
Add the drained can of mushrooms to the pan and heat through. Set the vegetable mixture aside to cool slightly.
Whisk the eggs and cheddar cheese together in a separate bowl until the yolks are fully broken, as if scrambling—season with salt and pepper to taste.
Fold the vegetable mixture into the egg mixture.
Grease a muffin tin and pour the egg-veggie mixture evenly into each cup.
Bake in the oven for about 20 minutes or until the eggs are set.
Serve the egg cups with fresh blackberries on the side for a delicious breakfast.
Notes
Protein content: ~ 7 g per egg cup
More Protein: Add sliced or crumbled sausage, bacon, or ground beef.
Serve with: Sauteed spinach, cherry tomatoes, plain whole milk Greek yogurt.
