To begin, preheat your oven to 200°F (95°C) to keep the quesadillas warm as you cook each batch. Prepare all your ingredients in advance, such as shredding the cheese and preparing any additional fillings like sautéed vegetables.

Heat a large skillet or griddle over medium heat. Add 1/2 tablespoon of vegetable oil or butter to the skillet and allow it to melt. Ensure the pan is evenly coated for frying the tortillas.

Place one tortilla in the hot skillet and immediately sprinkle 1/4 cup of shredded cheese evenly over half of the tortilla. If you are adding optional fillings like mushrooms or jalapeños, add them on top of the cheese at this point.

Fold the tortilla in half, gently pressing down with a spatula to flatten it. Cook for 2-3 minutes, or until the bottom is golden brown and crispy.

Carefully flip the quesadilla over and cook the other side for another 2-3 minutes, or until both sides are golden brown and the cheese is fully melted inside.

Once cooked, transfer the quesadilla to a baking sheet and place it in the preheated oven to keep warm while you repeat the process with the remaining tortillas.

Continue frying the rest of the quesadillas, adding more oil or butter to the pan as needed. Adjust the heat if necessary to prevent burning and ensure even cooking.

To serve, cut each quesadilla into halves or quarters and arrange them on a serving plate. Garnish with salsa, guacamole, or a sprinkle of fresh cilantro for added flavour. Enjoy these traditional Mexican quesadillas with family or friends for a comforting, cheesy meal.