This casserole is simple and delicious, and makes a perfect snack during a picnic (bento anyone?)—you should use it as a basic idea for a casserole, since the pasta sauce is the stable and the most important piece of the meal. It's also a very tweak-able recipe! :-)
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!
There is literally no easier recipe in the world, that tastes so good and takes only few minutes to cook, including rice cooking time! I always do it during hot summer days, because it's a no-brainer.
You can serve it as a main dish with more fancy toppings, or as a side dish, but also it's a great addition to bento or a small snack!