Red peppers are my favorite vegetables—they are crunchy, but also can be cooked soft, and have a sweet aroma that you can twist easily with additional spices. I needed lately some pasta sauce, and decided to experiment with red pepper pesto sauce, it turned out amazing and I think you will like that too! :-)
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.
Bento is not only rice, but also other ingredients, like... pasta. This recipe came to life when I had some uncooked beef left-overs and just wondered what to do with them. Cooking them as a part of bento was a great idea!