Chicken Pot Pie with BISTO

Preheat oven to 425°C. Prepare and cook chicken, potato and mixed vegetables. In 2 quart saucepan over medium heat, melt butter and cook onion until tender, but not browned. Stir in BISTO, pepper and milk. Cook until mixture boils and thickens, stirring constantly. Add cooked chicken, potato and vegetables. Heat through. Spread flour on one pie crust. Place flour side down into a pie plate. Spoon chicken/gravy mixture into the crust. Cover with the second pie crust. Fold the edge of the upper crust over and under the lower crust, pressing them together. With a fork, make indentations along the edges. With a sharp knife, slice small cuts into the upper crust. Coat crust with egg wash if desired . To prepare egg wash, crack one egg into a bowl and beat with a fork. Add 2 tablespoons of water with a pinch of salt. Brush piecrust prior to baking. Bake 30 minutes or until pastry is lightly browned.