Texas oven brisket

Ingredients:

4 to 6 lb. fresh beef brisket, well trimmed
1 cup barbecue sauce
1/4 cup Worcestershire sauce
1/4 cup liquid smoke
1 teaspoon garlic powder
2 teaspoon celery salt
2 teaspoon lemon pepper
1 teaspoon salt
1 cup chopped onion
1/2 cup water

Preparation:

Preheat oven to 275 F.
In a large Pyrex baking dish, thoroughly mix all ingredients for sauce.
Put the brisket in the baking dish and turn it over once to coat it with the sauce.
Seal the dish with heavy-duty aluminum foil.
Bake at 275 F for 5 to 6 hours.
Remove from oven and allow to stand for 1 hour before slicing.
Slice across the grain and serve with sauce.