Ingredients
Makes about 1 1/3 cups (325 mL)

• 2 tablespoons (25 mL) unsalted butter
• 1/2 cup (125 mL) finely chopped celery
• 3 tablespoons (50 mL) finely chopped yellow onion
• 1 cup (250 mL) ketchup
• 2 tablespoons (25 mL) lemon juice
• 2 tablespoons (25 mL) sugar
• 2 tablespoons (25 mL) cider vinegar
• 1 tablespoon (15 mL) Worcestershire sauce
• 1 teaspoon (5 mL) dry mustard
• Freshly ground black pepper, to taste

1. In a medium saucepan over medium-high heat, melt butter. Add celery and onion and cook 2 to 3 minutes, stirring occasionally.
2. Add remaining ingredients and whisk together. Bring to a boil, reduce heat, cover and simmer 15 minutes.
3. Transfer to a bowl, cover with plastic food wrap and refrigerate until needed.

(From: Weber's Big Book of Grilling.  This classic is great on pork ribs, chicken and beef)