4 large eggs
2 tablespoons finely chopped onion, (red, white or yellow/brown)
Salt and pepper, to taste
1/4 cup fresh spinach, roughly chopped
8 grape or cherry tomatoes, halved
1/4 cup shredded mozzarella cheese
Preheat oven to 350°F | 180°C. Lightly spray a 12-cup capacity muffin tin with nonstick oil spray.
In a large bowl, whisk together eggs and onion. Season with salt and pepper, to taste.
Add egg mixture halfway up into each tin of a greased muffin tin.
Divide the three topping combinations into 4 muffin cups each.
Bake for 15-20 minutes, until set.
Let cool slightly, then serve OR store in an airtight container in the refrigerator for up to 4 days and reheat when ready to serve.