Rice balls -- called "onigiri" in Japanese -- are traditionally a favorite food to pack in bento boxes. Their attractive shapes and portability make them ideal for lunches on the go, and most rice balls are nicely sized for toddlers to easily pick up and munch.

In Japan, onigiri are made with lightly salted rice and usually feature a savory filling. They can be made very quickly by using a rice mold.

Rice molds are an inexpensive bento tool that can be found in a variety of shapes. Triangle, barrel and ball shapes are traditional, while flowers, hearts and animal shapes appeal to kids.

To use a rice mold, pack cooked rice up to the top of the base piece, then press the lid on tightly to compact the rice. I usually use the leftover long grain rice that we regularly eat with dinner to make rice balls for my children. Instead of packing it into a food storage container after our meal, I just put it right into molds so I can quickly put it in bento boxes in the morning. The rice in these photos was brought home in a doggie bag from a meal out at a Japanese restaurant, and it has a little teriyaki sauce mixed into it. My boys gave this combo a big thumbs up.

When you're ready to remove the rice from your mold, press the small circle on the back and the rice will pop right out.

If you like you can use them as is. Cute, right?

You can also kick the cute up a notch by adding a little bit of nori (the seaweed wrapped around sushi) as decoration. You can find nori at well-stocked grocery stores or Japanese markets.

In addition to the rice ball, you'll need a paper punch (found at any craft store) and a small piece of nori. I find it's helpful to trim the thinner edges of the nori with kitchen shears so that the piece you're punching is of an even thickness.

Turn the craft punch over so that you can see the cutting edge, then slide the nori in until it completely covers the image and punch your shape out.

To adhere your nori shape to the rice ball, wet your finger with a little bit of water and rub it on the rice where you want the image to go. Press the cut-out into the wet area and rub your finger over it until it sticks.

Ta da! Now you have a super cute rice ball to add to your bento box!