Heat a large skillet over medium high heat and add olive oil or spray. Place tortilla in pan and heat until it is warm, flipping sides around 10-15 seconds.
When the tortilla is heated add your ingredients: cheddar cheese, zucchini, corn, red onion and then a little more cheddar cheese. Take care not to layer the ingredients too thickly. Season with salt and pepper.
Place another other tortilla on top. Press down with spatula.
Let cook for about 1-2 minutes until cheese begins to melt and then carefully flip the quesadilla over on the other side to brown.
Remove from pan when the cheese is melted and tortillas are browned on both sides.
Remove from heat and cut into wedges. Repeat with other tortillas.
Enjoy with salsa and guacamole