With my step kid I've basically just told him I'm not making anything else for him if he doesn't like what I made. If he won't eat it, he can have fresh vegetables and/or last night's leftovers instead. I give him some options before I start cooking, so he knows and has some say in what dinner is.

The exception is if I make something that's objectively gross. I've had a few frozen package dinners that looked good but were outright nasty and made sandwiches instead.

When I was little, I had times where I just straight up slept at the dinner table because I refused to eat. My parents learned quickly that if they didn't want me to starve to death, they were gonna need to make foods I actually liked.
Once they'd been doing that for a while, I got a lot more open to trying new foods, even ones I didn't like before, because now everyone else was eating and enjoying food I didn't have and I wanted to be a part of that. Didn't make me automatically like everything, but it did open me up to a lot of healthier options.