- 2 6-ounce packages albacore tuna packed in water, drained
- 3/4 cup mayonnaise
- 1/2 cup chopped green onions
- 1/4 cup diced seeded English hothouse cucumber
- 1/4 cup minced fresh dill
- 1/4 cup drained capers
- 2 tablespoons Dijon mustard
- 2 tablespoons minced fresh tarragon
- 12 1/3-inch-thick slices olive bread
- 1 cup arugula
- Mix tuna, 1/4 cup mayonnaise, and next 6 ingredients in medium bowl to blend. Season with salt and pepper. Divide tuna salad among 6 bread slices; top with arugula leaves. Spread remaining mayonnaise on remaining 6 bread slices; place atop arugula. Cut sandwiches in half; wrap each tightly in plastic wrap. (Can be made 1 day ahead. Refrigerate.)