Indian Samosa Pie

1. Preheat the oven to 375 degrees F (190 degrees C).

2. Whisk all-purpose flour, pastry flour, and salt together in a bowl. Drizzle 2 tablespoons vegetable oil into flour mixture while stirring until clumps form. Stir cold water, 1 tablespoon at a time, into the dough until it holds together; shape into a ball, cover with a damp towel, and set aside.

3. Place potatoes into a large pot and cover with salted water; bring to a boil. Reduce heat to medium-low and simmer until tender, about 15 minutes; drain. Transfer drained potatoes to a large bowl and mash until only small chunks remain.

4. Stir mustard seeds, curry powder, ground ginger, cumin, and red pepper flakes together in a bowl.

5. Heat 1 1/2 teaspoons vegetable oil in a skillet over medium heat. Cook and stir onion, carrot, and garlic in hot oil until carrot is tender, about 5 minutes.

6. Move onion mixture to one side of the skillet. Pour seasoning mixture into the skillet and cook until spices are toasted and fragrant, about 30 seconds. Stir onion mixture and spice mixture together; add vegetable broth and peas to the skillet and stir.

7. Fold carrot mixture into mashed potatoes; add sugar, stir, and season with salt and pepper. Spread the filling into a 9-inch pie plate.

8. Turn dough out onto a lightly floured work surface; roll out into an 11-inch circle. Place dough atop pie filling, pressing down on dough in several spots to remove any pockets of air. Trim excess dough from edges. Crimp edges of dough with your fingers. Cut a large 'X' in the center of dough to vent steam. Brush milk over dough.

9. Bake in the preheated oven until crust is golden brown, 40 to 50 minutes. Cool pie 5 minutes before serving.

Cook's Notes:

Cooking-from-frozen instructions: Preheat oven to 375 degrees F (190 degrees C). Place casserole on a baking sheet and cook until filling bubbles and crust is golden, bake for 75 to 90 minutes. Let stand 5 minutes before serving.