For the pastry:
- 1 1/2 cups all-purpose flour
- 1/2 tsp. salt
- 6 Tbs. (3/4 stick) unsalted butter, cut into
- 1/4 cup vegetable shortening
- 3 to 4 Tbs. ice water
For the filling:
- 3 cups turkey or chicken stock
- 4 thyme sprigs
- 1 bay leaf
- 15 pearl onions
- 4 Tbs. (1/2 stick) unsalted butter
- 1/4 cup all-purpose flour
- 1 carrot, peeled and cut into 1/2-inch pieces
- 1 celery stalk, cut into 1/2-inch pieces
- 3 small red potatoes, cut into eighths
- 2 cups cooked turkey, cut into 1/2-inch pieces
- 1/2 cup peas
- 4 oz. white button mushrooms, cut into 1/2-inch
- Salt and freshly ground pepper, to taste
To make the pastry, in a food processor, combine the flour and salt and pulse once to mix. Add the butter and vegetable shortening and process in short pulses until pea-size crumbs form, 25 to 30 seconds. While pulsing, add the water 1 Tbs. at a time until large, moist crumbs form, 10 to 12 seconds. Serves 4 to 6.
Turn the pastry out onto a lightly floured surface and shape into a flat disk. Cover with plastic wrap and refrigerate for at least 1 hour.
Preheat an oven to 400°F.
To make the filling, in a small saucepan over medium heat, bring the stock, thyme and bay leaf to a boil. Remove from the heat and let cool. Remove the thyme and bay leaf and discard.
Bring a large saucepan half full of salted water to a boil over high heat. Add the pearl onions and cook for 2 minutes. Drain the onions, rinse under cold water and drain again. Trim off the root ends, then cut a shallow "X" into each trimmed end and slip off the skins. Set aside.
In a large saucepan over low heat, melt the butter. Add the flour and cook, stirring, about 1 minute. Whisk in the reserved stock, increase the heat to medium-high and bring to a boil. Continue boiling, whisking often, until thickened, about 2 minutes. Reduce the heat to medium-low and add the carrot, celery, potatoes and pearl onions. Cook, stirring occasionally, until the vegetables are tender, about 25 minutes. Add the turkey, peas and mushrooms and cook until the mushrooms are tender, about 5 minutes. Season with salt and pepper. Transfer the filling to a 9-inch deep-dish ceramic pie dish.
On a lightly floured surface, roll out the pastry into a 12-inch round about 1/8 inch thick. Arrange the pastry evenly over the filling and trim the edges, leaving a 1-inch overhang. Fold under the excess dough and flute the edge decoratively with your thumb. Make 4 or 5 slits in the top to allow steam to escape. Place the dish in the oven on a piece of aluminum foil to catch any spills.
Bake the pot pie until the crust is golden and the filling is bubbling, 30 to 35 minutes. Let stand for about 5 minutes before serving.