In a small saucepan over low heat, combine the oil, apple, honeydew, mango, garlic salt, Worcestershire sauce, kosher salt, hot pepper sauce to taste and ground black pepper.
Heat for about 5 minutes to get warm. Place the steak in a shallow nonporous dish. Cover with the marinade and refrigerate, covered, for at least 3 hours. Flip steak over halfway through marinating.
Preheat an outdoor grill for high heat and lightly oil grate.
Grill steak for 10 minutes per side, dousing with remaining marinade, if desired. Steak is done when internal temperature reaches at least 145 degrees F (63 degrees C).
