Leftover Thanksgiving Casserole Recipe (Turkey, Mashed Potato, and Puff Pastry Pie)

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Leftover Thanksgiving Casserole Recipe (Turkey, Mashed Potato, and Puff Pastry Pie)

Leftover Thanksgiving casserole layers turkey, mashed potatoes, broccoli, and an easy cheese sauce into a savory pie topped with golden, flaky puff pastry. If you don't have turkey on hand, you can use rotisserie chicken. It's a delicious way to make leftovers into a completely different meal!

Course Main Course

Cuisine American

Keyword Leftover Turkey Pie, Thanksgiving Casserole, Thanksgiving Casserole Recipe, Turkey Puff Pastry Pie

Prep Time 20

Cook Time 40

Servings servings

Calories 447kcal

Author Faith Gorsky

Ingredients

Butter to grease the dish
3 tablespoons unsalted butter
1 medium onion diced
2 cloves garlic minced
3 tablespoons all-purpose flour
1 cup milk at room temperature
1 teaspoon Dijon mustard
1 teaspoon Worcestershire sauce
1/4 teaspoon smoked paprika
1/4 teaspoon salt
1/8 teaspoon black pepper
6 ounces sharp cheddar shredded
2 cups leftover mashed potatoes or leftover prepared stuffing (see Notes)
2 1/2 cups cooked chopped leftover turkey or chicken
3 1/2 cups cooked broccoli florets (see Notes)
1 sheet frozen puff pastry thawed in the fridge overnight (I used 1/2 of a 17.3 oz package)
1 egg lightly beaten with 1 tablespoon water (for egg wash)

US Customary - Metric

Instructions

Prep. Preheat oven to 400F. Grease an 8 by 8-inch casserole dish with butter.
Make the cheese sauce. Add the butter to a medium saucepan over medium heat. Stir in the onion and cook until softened, but not browned, about 5 minutes, stirring occasionally. Add the garlic and cook 1 minute more, stirring constantly. Add the flour and cook 1 minute. Whisk in the milk, Dijon, Worcestershire, paprika, salt, and pepper, and bring to a simmer, whisking frequently. Turn off the heat and whisk in the cheese a handful at a time until smooth. (TIP: Let the cheese sauce cool a bit so that the puff pastry isn’t going on top of hot sauce, which may cause it to not rise properly.)
Assemble the casserole. Spread the mashed potatoes in the bottom of the prepared dish. Spread the chopped turkey evenly on top of the mashed potatoes, and then spread the broccoli evenly on top of the turkey. Top with the cheese sauce, and spread it out evenly as best you can.
Top with the puff pastry. Unwrap the thawed puff pastry and place it on top of the casserole, tucking the sides down into the dish. Brush a little egg wash on top (there will be extra; don't try to use it all), and cut a few slits in the top of the puff pastry for the steam to vent.
Bake. Bake until the pastry is puffed and golden, about 25 to 30 minutes. Cool slightly before cutting and serving.

Video

Notes

Mashed Potatoes: Taste the leftover mashed potatoes and add salt and pepper as necessary. They should be dry, but if they’re very dry and crumbly, stir in a little milk (don’t add too much though; they should not be soupy!). Or if you don’t have leftover mashed potatoes, you can buy mashed potatoes at the grocery store.
If You Don’t Have Leftover Broccoli: You can use frozen broccoli (thawed, drained, and patted dry). Or you can blanch the broccoli. To do so, you will need 1 pound of raw broccoli (about 4 cups of chopped broccoli florets). To blanch it, bring a pot of water to a rolling boil. Season the water with salt, add the broccoli, and cook until crisp-tender, about 1 1/2 to 2 minutes. Drain the broccoli and set aside to cool.
Storage: Store leftovers covered in the fridge for up to 4 days.

How to Freeze:

Assemble the casserole, but don't put the puff pastry on top.
Let the casserole cool to room temperature.
Wrap the entire casserole well with plastic wrap.
Freeze it for up to 3 months.
The night before you want to make this turkey puff pastry pie, put it in the fridge to thaw overnight along with a sheet of puff pastry.
When you want to bake it, put the puff pastry on top of the thawed casserole and bake as directed.

Nutrition