My friends mother adopted 7 kids. She was an expert at hiding. She would grind carrots and zuchini in the chopper and add to meat loaf and shaghetti sauces. Pureeing cauliflower will mix into mashed potatoes. You can even add babyfood vegetables and fruit, already pureed, to things like cakes and brownies. I used to put them in casseroles when my oldest was young, it worked. The most important thing I have done is my rule, 2 bites chewed and swallowed before you can say you dont like it. No spitting out or gagging. My aunt used to call it a No THank You serving. Now after he found some things he really likes that he otherwise wouldnt have tried, he is more willing to try.