Heat olive oil in a skillet over medium heat until it shimmers slightly

Add chopped broccoli, bell pepper, and scallions, stirring until softened and lightly fragrant

Sprinkle in a pinch of salt while cooking to enhance the vegetables’ natural flavor

Remove the vegetables from heat and allow them to cool slightly so they don’t scramble the eggs

In a mixing bowl, whisk eggs until smooth and slightly frothy

Add milk, Parmesan cheese, remaining salt, and black pepper, mixing until well combined

Fold the cooked vegetables into the egg mixture, ensuring even distribution

Pour the mixture evenly into each muffin cup, filling about three-quarters full

Bake until the tops are set and slightly golden, and the centers feel firm to the touch

Let the muffins rest for a few minutes before gently removing them from the tin