Have you tried letting him help you cook? Maybe if he's part of it he might eat something? I have recently let Lily stand on a chair and 'help' me. For example, When I make sandwiches, I give her things like some cheese, peice of bread and a spoon or fork and she can do what she will with it. Or at dinner time from a salad she gets lettuce, grated carrot and cucumber slices and a bowl or two. There's usually a free flowing sippee cup of water or milk in there too and it all ends up drenched, but she often tries some of the food I give her before she ruins it! And even then she still eats the soggy bread or whatever (ugh!!). But even if he doesn't eat any of it, at least he's having fun with food rather than it being stressful or having to eat it if he doesn't want to, kwim??
Good luck!