Preheat oven to 400 degrees. Place baking sheet on lowest rack to catch any spilled juices.
In a large dutch oven over medium high heat, saute bacon until browned. Add onion and cook until softened. Add butter and garlic. Once butter is melted, add carrots and mushrooms. Cook until veggies begin to soften.
Add flour to veggies and stir for 1-2 minutes. Add chicken stock and scrape up any bits stuck to the pan. Add milk and half-and-half and let mixture thicken. Add salt and pepper, frozen peas, chicken and parsley.
On a clean floured surface, roll each dough disk into a 12-14 inch circle. Roll dough onto rolling pin and transfer to 10 inch pie plate pressing dough into the sides and bottom or plate.
Pour filling mixture into pie plate lined with bottom crust. Top with top crust. Pinch and flute edges. Cut slits in the top crust and brush with half-and-half. Use pie shields or foil placed around crust edges to prevent overbrowning.
Bake on middle oven rack for 40-45 minutes. Let stand 20-30 minutes before slicing. (It's easier to reheat pie than to cut when too hot--filling will run)