Combine beef with marinade; let stand 20 min. Heat oil in a wok or large skillet until very hot. Remove bbef from marinade and add to oil; stir-fry until brown (abt. 2 min). Remove and drain. Remove all but 1 Tbs oil, reheat il and add chili peppers; stir-fry 10 sec. Add beef, orange peel and seasonings. Stir-fry 4 min, mixing well. Serve at once.