In a small bowl, mix together chili powder, pepper, and salt. Set aside. In a large bowl, whisk together ketchup, mustard, vinegar, Worcestershire, lemon juice, steak sauce, molasses, honey, hot sauce, brown sugar, and tamarind paste.
In a large saucepan, heat canola oil over medium heat. Add onion, and saute for 5 minutes. Add garlic, and saute for 30 seconds. Add the chili powder mixture, and cook for 2 minutes, stirring constantly. This helps to release their oil-soluble flavors and gives the sauce more depth. Add the wet ingredients, and simmer for 15 minutes with the lid off. The sauce will thicken during this time. Taste the sauce, and adjust seasonings. I ended up adding an extra squirt of both honey and molasses since I like my BBQ sauce sweet.
If you don't want chunks of onion and garlic in your sauce, pass the sauce through a mesh strainer. I just left them in since I liked the texture it added.
2 tablespoons chili powder
1 teaspoon ground black pepper
1 teaspoon salt
2 cups ketchup
1/2 cup yellow mustard
1/3 cup apple cider vinegar
1/3 cup Worcestershire sauce
1/4 cup lemon juice
1/4 cup steak sauce
1/4 cup molasses
1/4 cup honey
1 teaspoon hot sauce
1 cup packed dark brown sugar
2 tablespoons tamarind paste*
3 tablespoons canola oil
1 medium yellow onion, finely chopped
4 cloves garlic, finely minced