A few people have asked, so here is the basic recipe that I started using recently. This makes a tangy sauce with a nice balance of flavors.
• 1 cup of ketchup
• 6 tablespoons brown sugar
• 4 tablespoons vinegar
• 4 tablespoons Worcestershire sauce
• 3 tablespoons lemon juice
• 1 teaspoon dry English mustard
• 1 clove garlic, crushed
• A pinch of salt and pepper
• Chili powder or Chili Sauce to your taste.
Combine everything in a bowl and whisk until the dry mustard and the brown sugar have dissolved into the liquid ingredients. Pour the mixture into a saucepan, bring to a boil and simmer for 30-45 minutes until you have a nice thick sauce.