Stop trying.
Put the food out, take the food away. No comments about food in between. It won't be a battle if you don't care if the child eats.

The older the child the harder it is as they are used to things the way they are used to them. But in time the child will come to accept that you serve what you serve and he can eat what he choses to eat (from what you have served).

Begging, bribing, asking, pleading just lead to battles because you WANT them to eat something. Just serve and clear.

I do make sure there is one "safe" food at each meal so my picky eater eats something. Once they have a bit of their 'safe' food in their belly to take off the edge of hunger they are a bit more willing to eat other foods. I also make the kids stay ta the table until the meal is done. So they are stuck sitting, watching their friend eat everything...which helps them eventually try things.

If the child is eating at snacks they will not starve by skipping lunch. The child will not starve by skipping lunch and snacks...they will eat eventually, even if it means in the car on the way home when the parents gives them their favorite snacks to make them happy.