Preheat oven to 350° . Line rimmed baking sheet with foil. Place metal rack on sheet. Sprinkle ribs all over with salt & pepper. Place meat side down, on rack. Press chiles through sieve into small saucepan (discard solids in sieve). Add remaining ingredients to pan. Stir to blend over medium heat until sauce comes to a boil. Season sauce to taste with salt. Transfer 1/2 cup sauce to small bowl & reserve. Brush ribs with 2 tbs sauce from pan. Turn ribs over & repeat. Roast ribs until very tender, brushing with sauce every 30 minutes, for about 1 1/2 hours. Cut rack into individual ribs. Serve ribs with reserved sauce.