First, prep all the filling ingredients: slice the fresh mozzarella, chop the herbs, and cut the tomato into 1/2-inch dice. Grate the Parmesan or Asiago cheese finely if you haven’t already.

Make the omelets: Heat 1 teaspoon oil in a 10-inch non-stick skillet over medium-high heat until the oil begins to shimmer. Break two of the eggs into a small bowl and whip them with a fork or whisk until slightly foamy. Add one tablespoon milk, cream, or water if desired and whip until combined.

Add the eggs to the hot pan and immediately begin pushing the eggs toward the center of the pan, tilting the pan to allow any liquid egg flow into the space you’ve created. Repeat two or three more times at 10-second intervals until no liquid egg remains.

Begin building the omelet: Distribute half the slices of fresh mozzarella over one half of the omelet, tearing it into smaller pieces, followed by the diced tomato, herbs, and finely grated Parmesan or Asiago cheese. When the omelet is set to your liking, carefully fold the unfilled side over the filling, pressing lightly with a spatula to ensure it holds together. Slide the finished omelet onto a serving plate.

Repeat with the remaining eggs, liquid (if using), and filling. Serve hot.