We are very careful not to force things. We'd ask him if he'd like to try something, and rarely he would. Peas were one thing that he admitted he didn't mind that much, so now when we have them he has to eat them. If we didn't mandate some things he'd be living on cheese and bread.

Things that he doesn't like can't be forced down his throat. He will throw up pretty much the instant the food hits his mouth, and sometimes before. He has a highly practiced gag reflex. :-P

Fortunately, if you're going to pick one vegetable to eat, pumpkin is a pretty good choice.