Hello reei,
My first time to post on Brillkids. My wife (aangeles) ans I have been having a great adventure raising our now 28 month old Ella. I noted your interest in bento recipes and thought that that would be a nice approach to get your picky eater to be more interested in the food you are serving. Having spent some time in Japan I too have a keen interest in Japanese cuisine. The websites that my my wife had previously referred to are pretty good. There's a nice youtube site I stumbled upon (http://www.youtube.com/user/cookingwithdog#p/u/25/-_hbPLsZvvo) that has a good short video on how to prepare a bento lunchbox. You'll just have to get used to the quirky voice over and the fact that this show is hosted by a well-groomed poodle (ha-ha-ha!).But the recipes are pretty well demonstrated and there is a complete list of ingredients shown at the end of each video. You might want to try the other recipes on there, too.
I have had a great interest in cooking but much more since we had Ella. Beyond fulfilling her nutritional requirements, I've began to look at food as another tool for teaching Ella--from home safety (avoiding burns), science concepts (Where do eggs come from?), culture (what is Thanksgiving and why all the food??), geography (We're having paella tonight. It's a dish from Spain!), and manners (she likes saying/reading grace from a prayer card I typed out on a 4x6 index card before meals) . Nothing like a good meal to educate the little one.