Ingredients:
1 can of tuna (in water)
2 Tbs. plain Greek yogurt
1 tbs. mustard
salt/peper to taste
1/2 cup diced celery
3 Romain lettuce leaves (left whole)
Optional: other toppings such as tomatoes and cheese
Directions:
Drain tuna and mix all ingredients together. Scoop into lettuce leaves.