We have always made sure to include some things that he DOES like, no matter what we are making. I mean, I hate chili and I hate lamb and if someone presented me with either of those things for dinner, and then tried to get me to eat them at other times in the day, well I would go hungry for a good few weeks before I gave in and ate them (Probably close to the brink of starvation before I would give in!). I don't see it as any different with my DS, no matter his age. If I am making something that I know he likes and he refuses it, then it's different.
So tonight I made a stew that I know he hates and so it is not really fair for me to expect him to eat it. I still put it on his plate, and still told him he needed to try it, but I also made sure he had other things out as well, at the same time. I do give the other things at the same time and present it all as his dinner, so that he does not get the idea that if he does not like it I will go and make something new. But I make sure he is given choices that he does like. So tonight in addition to his bowl of stew he had a plate with carrots, corn, bread, and cheese. And he did actually try a few bites of the stew but spat them out - and ate the rest of his dinner.