Oyster Pie

2 (16 ounce) cans oysters or 2 pints fresh oysters
6 slices bacon
1/2 cup thinly sliced celery
1/2 cup finely chopped onion
1 (10 ounce) package frozen peas and carrots,
    partially thawed and broken apart
1/2 cup flour
1 1/2 teaspoons salt
1 teaspoon pepper
1 1/2 cups milk
1 cup diced cooked potatoes
1/2 cup diced pimiento

Topping
2 cups buttermilk biscuit baking mix
1/2 cup milk
2 tablespoons butter

Drain and reserve 1/2 cup oyster liquid. Cook bacon crisp; dice and save 2 tablespoons drippings. Cook celery and onion in drippings until tender. Stir in peas and carrots; heat well. Blend in flour and seasonings. Stir in milk and oyster liquid. Cook until thick, stirring. Fold in potatoes, pimiento, oysters and bacon; heat. Pour into a 12 x 8 x 2-inch baking dish.

Topping: Mix biscuit mix and milk. Roll and place squares on top of oyster mixture. Brush with butter. Bake at 425 degrees F for 15 minutes.