Step 5
Cook and stir onion, celery, bell peppers, and garlic in the Dutch oven over medium heat until soft, about 10 minutes. Add chopped tomatoes, 3/4 cup reserved tomato liquid, currants, raisins, curry powder, butter, bay leaves, salt, and black pepper; bring to a simmer, reduce heat to medium-low, cover the Dutch oven with a lid, and simmer until sauce is thickened, about 30 minutes.