Created by ellie on April 3, 2018
Step 1: Mix first 4 ingredients (yogurt - mustards) in a large bowl and mix in tuna. Add celery, onion and cilantro and dmix well. Cover and chill for at least 30 minutes.
Step 2: Spoon 1/2 cup tuna on each of 6 bread slices, top with tomato and arugula and bread slices. Cut sandwiches in half.