Toast the waffles: Toast the mini waffles until golden and crisp. Keep them warm on a plate.

Prep the eggs: Crack eggs into a bowl, season with salt and pepper, and whisk until smooth and slightly frothy.

Cook the eggs: Heat a nonstick skillet over medium heat and add butter or oil. Pour in the eggs and cook, stirring gently, until soft and just set. For neater sandwiches, form the eggs into four equal mounds or fold into squares.

Add cheese: Place cheese over the warm eggs to melt, or put cheese on a hot waffle so it softens while you assemble.

Assemble: Spread a thin layer of mayo, mustard, or maple syrup on half the waffles if you like. Top each with egg, cheese, and any add-ins. Cap with another waffle.

Finish and serve: Press lightly to help the cheese adhere. Serve hot, or wrap in foil for a grab-and-go breakfast.