Cut a lengthwise strip from each pepper. Chop enough of pepper strips to measure 1/2 cup; reserve remaining strips for another use. Remove and discard seeds from peppers. Cook peppers in boiling water to cover 5 minutes; drain and set aside.
Cook bean mix according to package directions, omitting fat and seasoning packet. Combine chopped pepper, bean mix, corn, and next 3 ingredients. Spoon evenly into peppers; place peppers in a 13- x 9- x 2-inch baking dish. Add hot water to dish to a depth of 1/4 inch. Bake at 350° for 20 minutes or until thoroughly heated.
Position knife blade in food processor bowl; add salsa. Process until smooth. Spoon salsa onto plates; top with peppers.