Roast Barbecue

olive or vegetable oil
12 lbs english shoulder or chuck roast
3 large onions, chopped
2 Tbsp vinegar
6 Tbsp fresh lemon juice
2 1/4 cups water
6 celery ribs, chopped
6 cups ketchup
1/2 cup worcestershire sauce
6 Tbsp brown sugar
3 Tbs prepared mustard
6 Tbsp chili powder
2 tsp ground black pepper

Preheat oven to 350 degrees.  In a large skillet or dutch oven over medium-high heat, heat oil.  Individually brown roasts on all sides and transfer to large roaster. 

In a large container, mix all other ingredients.  Pour over roasts.  Cover & roast approximately 3 hours.  Remove beef & shred with fork, removing fat & gristle.  Return meat and continue roasting until meat is very tender (approx 2 more hours). 

Yields 6 meals, 24 servings total, approx. 1 cup per serving