Ting-Town Barbeque Beef Sandwich

Ingredients (15)

• + 3 stalks celery, sliced thin add to pantry
• + 1 large onion, coarsely chopped add to pantry
• ✓ 4 cloves garlic, minced
• ✓ 1 cup ketchup
• + 1 cup barbeque sauce add to pantry
• + 1 tablespoon prepared yellow mustard add to pantry
• + 1 cup beer add to pantry
• + 2 tablespoons cider vinegar add to pantry
• + 2 tablespoons Worcestershire sauce add to pantry
• + 2 tablespoons brown sugar, packed add to pantry
• + 1 teaspoon chili powder add to pantry
• + 1 teaspoon salt add to pantry
• ✓ 1 teaspoon ground black pepper
• + 4 pounds boneless beef chuck roast, trimmed of fat add to pantry
• + 16 hamburger buns, split add to pantry