2 c. leftover roast beef, diced
1 lg. tomato, diced
1 med. white onion, diced
1 lg. red apple, diced
1 head lettuce broken in bite-size pieces
Juice of 1/2 lemon
Mayonnaise

Mix first 5 ingredients together, squeeze lemon juice over all. Mix with enough mayonnaise to coat. Add salt and pepper to taste. Serve with crackers.