Chicken Pot Pie

Name: Chicken Pot Pie
Prep time: 30 min
Cook time: 1 h
Total time: 1 h 30 min
Cuisine: American
Ingredients: 1 recipe Homemade pie dough (, chilled (our recipes makes 2 crusts, needed for this recipe; one for the top, and one for the bottom)); 1 pound boneless skinless chicken breasts; 1/3 cup butter ((75 g)); 1/2 cup celery (, sliced (50 g)); 1/3 cup onion (, chopped (45 g)); 1/3 cup all-purpose flour ((40 g)); 1/2 teaspoon salt ((2.5 g)); 1/4 teaspoon freshly ground black pepper ((0.5 g)); 1/4 teaspoon celery seed ((0.5 g)); 1/2 teaspoon garlic powder ((1.5 g)); 1 teaspoon chicken bouillon paste (, or more to taste (or substitute 1 bouillon cube) (5 g)); 1 cup milk ((240 ml)); 8 ounces frozen veggies ((mix of carrots, peas, green beans, and corn) (225 g)); 1 egg; 1 tbsp milk ((15 ml))