My kids aren't that picky when it comes to food. They eat vegetables and ask for seconds. I don't think we did anything special, except we set a good example by eating vegetables. I don't think that explains their open-mindedness entirely. One thing we have been very consistent about is encouraging our kids to try everything on their plates. If they don't like it, we say something like:
It's okay...Maybe your taste buds aren't ready for it yet...Maybe next time. Thanks for trying it.
This avoids the power struggles that many parents face when it comes time to eat.
And if all else fails sometimes an airplane (a/k/a fork filled with food) into the mouth works.
~Karen