In a small pan over medium heat, melt butter. Add apple pie filling, cinnamon, and nutmeg. Stir until warmed and combined.
In a small bowl, mix granulated sugar with cinnamon and set aside.
Lay out tortillas. Spoon the apple filling mixture onto half of each tortilla and fold them over.
Heat a nonstick skillet on medium. Spray or brush each quesadilla lightly with butter and cook for 2-3 minutes per side until golden brown.
Immediately sprinkle the hot quesadillas with cinnamon sugar.
Slice into wedges and serve warm with whipped cream or vanilla ice cream if desired.