Preheat oven to 350°F. Mix ground beef, ketchup, mustard and Gravy Mix in large bowl until well blended. Add ground beef mixture and onion to skillet. Cook and stir until meat is fully cooked. Gently fold in cream cheese and 1/2 cup shredded cheese.
Pour mixture into 2-quart casserole dish. Sprinkle with remaining 1/2 cup shredded cheese. Bake 10 to 15 minutes or until cheese is melted. Sprinkle with tomatoes and pickles.
Serve with steak fries, sesame bread sticks or sesame crackers.