We have a house rule: You don't like it? Have a sandwich or cereal.
That easy.
I love to cook. I'm the one cooking what I happen to be in the mood for. And even I sometimes end up going "Ick." and having something's else. Sometimes not even 'Ick' but just NOT wanting something so heavy /spicy/green/whatever. Everyone else can chow down, and I'll have some crispix, thanks.
If we actually start to starve... Then I'll act like it. Until then, a bowl of cereal or a Sammie is an acceptable alternative, and the uneaten portion just gets wrapped up with the rest of the leftovers.
I grew up in a house where food was a battle. In my house, we love food, and its never a battle. Sometimes my son might eat cereal all week. Sometimes he might not have Plan B for 6 months. Whatever. No biggie.
Oh. My son is 10. Starting around 2 or 3 is ALSO where the clause came in 'You have to make it yourself' (aka when he was capable of it).