Cut meat into chunks, 1 to 1 1/2 inches in size. Stem bell peppers and remove membranes and seeds. Cut peppers into large pieces, about 2 inches in size. Cut onions into 1 1/2 - 2 inch pieces. Thread meat, peppers, and onion in any pattern evenly onto 6 skewers. Place kebabs onto a baking sheet. Brush with sauce. Turn, and brush with sauce on the other side. Cover with plastic wrap and place in refrigerator. Chill 30 minutes.