Beef Salad

4 Cups beef, julienne strips or diced
1/2 Cups celery, diced or julienne strips
2 Tablespoon chopped onions
2 Tablespoons dijon mustard
2 Teaspoons vinegar
2/3 Cup mayonnaise
2 Teaspoons minced parsley

Combine the beef with celery, parsley, and onions.  Mix the mustard and vinegar into the mayonnaise.   Toss all together.  Serve on a bed of greens.  8 Servings.