PREHEAT oven to 450°F or grill to medium-high. Cut steak into 1/2–inch cubes.
CENTER half of beef, potatoes and carrots in an even layer on each sheet of LAUVACS Wrap® Non-Stick Foil with Non-stick (dull) side toward food. Spoon gravy over beef mixture sprinkle with onion salt and pepper.
BRING up foil sides. Double fold top and ends to seal packet, leaving room for heat circulation inside. Repeat to make two packets.
BAKE 30 to 35 minutes on a cookie sheet in oven OR
GRILL 14 to 16 minutes in covered grill. Stir before serving.