So a child won't eat a huge selection of foods, and the mother has decided that she's not prepared to cook the same thing every night. She will offer the child whatever the family is eating, and if they won't eat it, they'll go hungry.
I have a vivid memory of a school dinner which came around on the menu once a month. It was fish with a white sauce and tomato ketchup. The rule was that you had to finish your meal before you could go out to play. There was no choice of meal.
Even bringing the memory of that food back to mind is setting off my gag reflex. I have not eaten tomato ketchup since I left that school. So if their plan was to force me to eat certain foods because it would make me like them, their plan completely misfired.
Oh God, I've just remembered the custard tart thing which had what we described as pepper on top but I guess was cinnamon. That WAS possible to swallow, but only if you held your nose. Strangely enough, not a dish I have sought out in adulthood.
Ihad a friend who was fine with the fish and the custard tart, but his bugbear was the cheesecake. Generally he'd just sit in the dining room for the whole lunch time, but one time he was so desperate to go out and play that he took a mouthful and WAS SICK ALL OVER THE PLATE. His mum came in and tore the headteacher off a strip, and after that the rule changed and you no longer had to eat the food you didn't like (there still wasn't any choice though; just the one meal)
I'd be taking a completely different tack - rejoice at the veg and pasta and fruit and fishfingers - that's a balanced diet before you even start - and just offer other things on the plate or on a separate plate at the same meal time.
If there are things a child will often eat, but not if there's a bowl of pasta available, give them the other things five minutes before you produce the pasta, so they maybe have a bit of whatever else it was.
I'd be offering a selection of things which my child might want to eat in that meal, and the rejected ones I'd eat myself or pop in the fridge or freezer for another occasion.
I'd be aiming at a balanced diet over a week or month rather than every day. And of course my values would reflect in the kinds of things I offered - whether it was all organic tofu or there was a big concentration of chips, or whatever it might be. In that way, I'd be inexplicitly sharing my understanding of what good things and bad things are to eat. [nb I've never tasted tofu in my life but I had chips for lunch today...]
The theory bit
Why would you be punishing someone for not wanting to eat certain foods???? What precisely are you hoping to achieve by that? I just don't get it as a strategy for developing a balanced diet and adventurous palate. It certainly didn't work for me and my friends at primary school.
Worth thinking also about food as control and as battleground. If a person doesn't have control over food - they are forced to eat things they don't want and when they don't want to eat, in circumstances which they don't want to eat in, that can become a really really serious battleground later on. And in their teens, the way a person might well be taking control over that part of their lives if it's been a battleground through early childhood is through anorexia and bulimia and other eating disorders and binge/slim stuff. Maybe these hypothetical unintended consequences are too extreme and unrealistic, but I'd definitely be wanting to watch out carefully for whatever knock on effects this kind of battle might have both on my child's psyche and on our relationship.