DS went off his veggies for a couple of months so I hid them into things. But I started letting him "help" me cook. He is only just gone 20months so cant really do much lol, but when I am shopping I will hand him a bit of veggie. So say a broccoli. When we get home, he helps me put it away. Then later he watches/helps me wash it, then watches me cut it up. Then he helps put it in the pot (not hot lol). Afterwards I serve it to him, "Here is the broccoli we cooked!", and if he is still a bit hesitant I go and get the rest of the broccoli thats left for him to hold and explore again. Has worked a charm with broccoli and cauliflower so far.

I have also been told that young toddlers need at least 3 serves of veg OR fruit, it doesnt matter if its only fruit at this age. I think as long as you're offering, they have the opportunity to try it but I try not to stress if DS doesnt want it