Combine pork with 1/4 cup chicken broth, soy sauce, lime juice, sugar, coriander, and garlic powder. Toss to coat. Marinate 4 hours or overnight, stirring occasionally.
Thread meat alternately with peppers on 2 large or 4 small skewers. Broil 6 inches from heat 15 to 20 minutes, or until meat is tender and brown, turning skewers and basting occasionally with 6 tablespoons marinade.
Meanwhile, combine peanut butter, pepper, remaining 1/2 cup broth and marinade in small saucepan; cook, stirring, until smooth. Serve sauce with kebobs and beds of fluffy rice.