Loose Meat Sandwich - Space Burger

• 1 lb (.5 kg). lean hamburger
• 1 medium onion, chopped (walla walla sweets are the best)
• 1 stalk celery, chopped
• 1/2 cup (125 ml) shredded lettuce
• 1 tomato, diced
• mayonnaise, to taste
• mustard, to taste
• salt and pepper, to taste
• optional: grated cheese
• 4 or more pita breads

1. Brown hamburger well; drain off grease.
2. Put hamburger in bowl.
3. Add remaining ingredients; mix well.
4. Split or cut in half pita bread.
5. Fill pita with hamburger mixture.

lean hamburger, onion, celery, shredded lettuce, tomato, mayonnaise, salt, grated cheese

Taken from online-cookbook.com/goto/cook/rpage/001559 (may not work)