Like if I have cooked a pasta bake for the main would you consider 2 type sof veggies on the side he likes as ok and then if he eats only the veggies without touching the pasta its ok? and you would give him as much of the veggie he wants?
So if i am doing spag bol I would do a veg on the side and garlic bread so that to me is five things....the pasta, the sauce, the meatballs, the veg, the garlic bread. So both mine will readily eat the pasta and the meatballs. There is no more of those until they try the others. SO with your veggies, I would give a normal sized portion and if he requests more I'd say to try the pasta bake first and then you'll get him some more.
At that age though mine ate better depending on how it was served (wee monsters) so with spag bol, M ate it ALL if I put the sauce on the side in a bowl rather than dumped on top like I did with ours. She liked to be able to see all the components of what she was eating IYKWIM?!
and when I am tarveling I menu their food to things I knwo they will enjoy.
It must be hard with workign but I think when you start to change things up I would make the new eating rules ALL the time KWIM? So they are the same with you, daddy, nanny whatever so that he realises this is just how meals are as opposed to this is how meals are when mummy is here as i could see that potentially causing issues!