Heat a skillet over medium-high heat. While the skillet is heating, grate the Gruyère until you get about 1/3 cup. Bonus points for you if you already have your cheese shredded.
Place the tortilla in the pan. Spread the cheese onto one half of the tortilla. On the other half, layer the deli meat and and then the spinach.
While the quesadilla is cooking, slice the apple into thin slices. Place the sliced apples on top of the spinach.
When the Gruyère has melted and the tortilla starts to bubble (about 1-2 minutes), fold the cheesy half on top of the other half.
Serve on a plate and enjoy!