You've probably seen this tip before, and I'm here to tell you a couple things about letting kids pick the veggie:
Even at 20 months of age, it gives them a sense of empowerment — and sends a message that their opinion matters. (My son's verbal abilities are developing, but one thing I believe I can still communicate is respect for each family member's opinions.)
It doesn't guarantee that they'll try the darn thing. And even though this is sooo frustrating, it's still OK.
In this particular showdown, my kiddo picked mushrooms. Anything not-green always wins, by the way.