S.L.
I second the idea of presenting foods in different forms to see what he responds to. For example my son loves carrots and I cut some into sticks and steamed them for in his lunch, but everyday they came back home untouched. After a few days I tried cutting them into bite sized pieces and suddenly he ate them (it turns out he doesn't like finger foods anymore, he wants to eat everything with a fork like a big boy).
My son also loves pancakes, burritos and quesadillas. I can put any veggie into any one of them and he eats them up. I make a big batch of pumpkin or spinach pancakes and freeze them for his lunch or snacks on days were I'm low on time.
weelicious.com is also a good website for creative, kid friendly recipe ideas.
Just remember that some kids have to be presented with certain foods as many as 15 times before they will even give them a shot. Familiarity is key with toddlers.