Preheat the oven to 350 degrees F. Lightly coat 4 (8-ounce) ramekins with cooking spray.
In a large bowl, combine the turkey, gravy, peas, and carrots. Divide the mixture between the ramekins. Top each with 1/2 cup mashed potatoes. Do not over-smooth the tops; the peaks will brown for a pretty finish. Bake for 20 to 30 minutes, until bubbling and the tops are golden.