Kansas City-Style BBQ Sauce
2 Tablespoons Butter
1 Small yellow onion, finely chopped
3 Cloves Garlic, minced
2 Cups Ketchup
1/3 Cup Molasses
1/3 Cup Dark Brown Sugar
1/3 Cup Apple Cider Vinegar
2 Tablespoon Yellow Mustard
1 Tablespoon Chili Powder
1 Teaspoon Freshly Ground Black Pepper
1/2 Teaspoon Cayenne Pepper
Melt butter in medium saucepan over medium heat. Add onion and cook until softened, about 5 minutes. Add garlic and cook until fragrant, about 30 seconds.
Add ketchup, molasses, brown sugar, vinegar, mustard, chili powder, black pepper, and cayenne pepper and stir to combine. Bring to a boil, then reduce heat to low and simmer until slightly thickened, about 30 minutes, stirring frequently.
Transfer sauce to a blender and blend until smooth. Let cool to room temperature, transfer to a jar and store in refrigerator for up to a month.