TIP: Make filling up to 3 days in advance and refrigerate until ready to use.
- Heat olive oil. Sauté leeks in a non-stick frying pan until softened and lightly browned, 2-3 minutes.
- Add mushrooms and celery and sauté until cooked through and browned, 6-8 minutes. Season with salt and pepper to taste.
- Deglaze with white wine.
- Sprinkle cornstarch over vegetable mixture.
- Add turkey broth and mix thoroughly. Bring to a gently simmer and continue to stir until broth thickens to a gravy. Remove from heat.
- Mix in leftover turkey.
- Spray small ovenproof containers with non-stick cooking spray.
- Generously fill each container with turkey vegetable mixture.
- Top each container of turkey mixture with puff pastry.
- Bake according to package directions.