I put veg in omelettes and also risotto, adding a bit of cheese so it disguises the taste (and it's more nutricious), other than that, the oly veg dd will eat it's cherry tomatoes.
Sometimes fruit with icecream works, or a fruit salad with a bit of sugar and freshly squashed orange juice, but recently she's started to try and separate the icecream from the fruit!!!
Like your children she eats brilliantly at nursery of course!!!
Starofleo I wouldn't give him chocolate or custard to make, with dd I've noticed if she goes without eating one meal, she'll eat more at the next, so I try (hard) not to too get too stressed about it, but no matter how terrible her tantrums may be (and the are) I refuse to give her any kind os sweets instead of a meal. That's law for me, if she's eaten her dinner she can have all the icecream she wants, but if she's not hungry for dinner, she's not hungry for icecream.
I occasionally give her vitamin drops just to make sure she gets enough.
I think it's just another way toddlers have to asse their independence and the urge to go and play is an important factor too (esp. with DD). So I suffer in silence (when I manage) and hope it will go away (though I'm abit worried by the fact that moosh's ds is still doing this at 3.5!!!)