Finely chopped fresh thyme or rosemary, for garnish (optional)
Heat a large skillet over medium high heat. Add approximately 1 tablespoon of butter to the skillet and allow it to melt. When butter is melted, reduce heat to medium-low and add 1 tortilla to the skillet, making sure the entire bottom side gets coated in the butter.
Working quickly, place a small layer of grated cheese on top of the tortilla, followed by the chopped (or sliced) leftover turkey, sprinkle of cheese, layer of cranberry sauce and a final layer of cheese. Gently press the other tortilla on top and cover the skillet with a lid to help accelerate the cheese melting process.
When bottom is golden brown and cheese has melted, (very) carefully flip over the entire quesadilla and allow the remaining side to cook until golden brown.
Transfer quesadilla from skillet to cutting board and allow 1-2 minutes to cool before cutting. Garnish with fresh chopped thyme or rosemary, if desired.