Combine the tuna, yogurt, Dijon mustard, chopped walnuts, raisins, capers, parsley, salt, pepper and red pepper flakes (if using) in a mixing bowl.
Mix with a fork until evenly combined.
Place the handful of spinach leaves in the center of the flour tortilla, then dump the tuna fish salad right on top of the spinach.
Fold the tortilla over the salad and then push gently but firmly with your hand to form a roll.
Tuck the ends in and then finish rolling the tortilla into a tight wrap.
Slice on a diagonal and serve immediately, or wrap tightly in plastic film and consume within a day.
- 金枪鱼可以换成鸡肉 - Tortilla 可以换成bread - 葡萄干可换蔓越莓干