- 8 cups diced rhubarb (1-inch pieces)
- 1 red onion, cut into 8 equal wedges
- 9 cloves garlic
- 1 cup beer
- 1 cup brown sugar
- 1/2 cup ketchup
- 1/4 cup balsamic vinegar
- 2 tablespoons Worcestershire sauce
- 2 tablespoons chili powder
- 1 tablespoon liquid smoke
- 2 teaspoons salt
- 1 teaspoon ground cinnamon
- 1/2 teaspoon cayenne pepper
- Preheat oven to 450 degrees F (230 degrees C). Spread rhubarb, onion, and garlic on a baking sheet.
- Roast in the preheated oven until tender, about 15 minutes.
- Transfer roasted rhubarb, onion, and garlic to a blender; puree until very smooth.
- Pour rhubarb puree into a large pot. Stir in beer, brown sugar, ketchup, balsamic vinegar, Worcestershire sauce, chili powder, liquid smoke, salt, cinnamon, and cayenne. Simmer over medium heat, stirring occasionally, until sugar dissolves and flavors combine, about 15 minutes.