1. Preparation
Gather all ingredients: flour tortillas, shredded cheese, and optional toppings.
If using toppings like peppers or onions, wash and slice them into thin strips.
Set up a workstation with a cutting board and cooking utensils ready.
2. Cooking
Heat a skillet or frying pan over medium heat for about 2 minutes.
While the pan heats, place one tortilla on a plate.
Evenly sprinkle shredded cheese over the entire surface of the tortilla, covering to the edges.
If using, add sliced peppers or onions on top of the cheese.
Place a second tortilla on top of the filled tortilla.
Carefully transfer the whole quesadilla into the heated skillet.
Cook for 3-4 minutes, or until the bottom tortilla is golden brown and the cheese starts to melt.
Using a spatula, carefully flip the quesadilla over and cook the other side for another 3-4 minutes.
When both sides are golden brown and the cheese is fully melted, remove the quesadilla from the skillet.
Allow it to cool for a minute, then cut into wedges and serve with salsa or guacamole if desired.