I know the picture doesn't do this justice - trust me, it's delicious!
The recipe here is for a traditional 9" pie dish, but you can easily double it and bake it in a 9x13 baking dish, as my friend did when she brought it to us. Our family was able to eat it for TWO nights (what a friend!), so if you have a large family or group, that should work great!
Chicken Pot Pie
6 T. butter, divided
1 1/4 c. onion, diced, divided
1 c. carrots, diced
1 c. celery, diced
3/4 c. frozen peas
1/4 c. flour
2 c. chicken broth
2 c. cooked chicken, diced or shredded
1/4 tsp. celery salt
1 tsp. salt, plus more to taste
1/2 tsp. pepper, plus more to taste
1 1/4 c. all-purpose or whole white wheat flour
1/4 tsp. salt
8 T. (1/2 cup) cold salted butter, diced
up to 1/4 c. ice water
For the crust: combine flour and salt in mixing bowl or food processor. Add butter and pulse a few times if using a food processor, or blend into the flour with a pastry blender, fork and knife, or your hands until well-distributed. Butter should be pea-sized or smaller. Slowly drizzle in the ice water, tossing with your hands or pulsing in the processor until the dough starts to come together easily without crumbling. Gather into a ball, wrap in plastic wrap, and chill in the refrigerator for 30 minutes.
For the filling: Preheat oven to 350 degrees. In a large skillet, melt 2 T. butter over medium high heat. Add 1 cup onion, along with the carrots and celery, and cook, stirring often, until soft, about 5-7 minutes. Add peas, and stir until warmed through. Season with celery salt, 1/2 tsp. salt and 1/4 tsp. pepper. Remove vegetables to a plate and set aside.
Add remaining 4 T. butter to skillet. Add remaining 1/4 c. onion and cook for about 3 minutes, until slightly softened. Add flour, stirring constantly for about 1 minute. Whisk in the chicken broth slowly. Continue to cook, stirring constantly, until thickened, about 5-7 minutes. Season with salt and pepper, to taste (start with about 1/4 tsp. of each).
Remove from the heat and add the vegetables back into the skillet along with the cooked chicken. Stir until well-coated. Transfer to a pie dish or an 8x8 baking dish.
Remove pie crust from the refrigerator and place on a floured surface. Roll out the dough until large enough to fit the top of your pan. Roll up with your rolling pin, and unroll over the filling in the pie dish. Trim, tuck, and crimp the edges. Cut a few slits in the crust to allow air to escape.
Bake at 350 degrees for about 30-35 minutes, until top is golden brown and filling is bubbling. Remove from the oven and let cool about 5 minutes before serving.
Source: My friend Amber Thompson & King Arthur Flour pie crust