One thing that I like about living in Germany is that during the Christmas time, locals cook and bake many delicious local dishes — one of them is Vanille-Kipferl, also known in other countries as Italian cornetti, French crossaints, or Polish rogaliki. But however you call them, they are basically very crispy cookies covered with vanilla sugar. And for this simplicity I absolutely love them :-)
Tuna paste is ridiculously easy to prepare and makes a great no cooking bento, cutting the preparation time to less than 20 minutes, including rice cooking time! Now, that's what I would call cooking on the go! You can also use the tuna paste for a great tasting onigiri or sushi.