A.B.
My 4 year old is the same way. He doesn't care at all about food. He wants to eat things in 2-3 bites all day long. What I've done is set a schedule for dinner time that's at 6 pm sharp. We all eat at the table together, and he's not allowed to get up until he's done. His reward when he's all finished is cartoons (so he usually focuses on eating so he can go watch tv). It's bribery, but it's working! Also, just in the last couple weeks, I've started enforcing the policy of "you will not eat again" after supper. It took a few days when he cried before bed that he was hungry, but we didn't give in. Now he knows if he doesn't want to be hungry later he has to eat. Good luck.