In a mixing bowl, crack the eggs and add milk, salt, and pepper. Whisk them together until the mixture is well combined and slightly frothy.

Place your non-stick skillet over medium heat and add butter. Let the butter melt and bubble, but avoid browning it.

Once the butter is hot, pour the egg mixture into the skillet.

Allow the eggs to cook for a minute without stirring.

With a spatula, gently lift the edges of the omelette to let uncooked egg flow underneath.

When the edges are set but the center is still slightly runny, add your desired fillings to one side of the omelette.

Using the spatula, carefully fold the omelette in half over the fillings.

Let it cook for another minute to warm the fillings through.

Slide the omelette onto a plate and serve it warm.