Begin by heating a large nonstick skillet over medium heat. Add a tablespoon of olive oil or butter, allowing it to melt and coat the bottom of the skillet.

On a clean surface, lay out one flour tortilla flat. Sprinkle mozzarella cheese on one half of the tortilla, followed by pepperoni slices and any optional toppings.

Carefully fold the tortilla in half, pressing gently to secure the fillings within. Ensure the edges align properly.

Place the folded quesadilla in the hot skillet and cook for about 2-3 minutes on one side until golden brown, then flip to cook the other side.

When both sides are crisp and the cheese has melted, slice the quesadilla into triangles and serve warm with marinara or pizza sauce for dipping.