Omelet rice lunch box and spaghetti lunch box are all great! I bought the cutlery set "Slim Trio Set Chopsticks Spoon Fork Set" sold by skaters.
As the name implies, this product is a set of chopsticks, spoon and fork. You can carry it compactly by stacking it in a case with a size of about 18.8 x 3.7 x 2.7 cm. Since the bottom of the case has a "silicone cushion" that absorbs shocks, it is also characterized by the fact that it does not make a rattling noise even when shaken. It makes the time to carry a little more comfortable.
It is sold on various mail order sites, and the price on Amazon.co.jp was 756 yen. There are also models with colors and illustrations other than the "yellow" introduced this time, so if you are interested, please check it out. It may be said that it is more suitable for adults than small children because it was necessary to put some effort into closing the case, probably because of individual differences in the products.