Many thanks to you all for your supportive comments. Much food for thought! It’s good to know lots you have had similar experiences.
I will definitely try to involve him more with the prep and cooking of things, especially as I grow a lot of veg and fruit so that is a good idea.
I will not let it become an issue that affects his time spent with me as he is a happy healthy child with loving parents and that is the most important thing, in a world where many children are not. I just want to help both him and my daughter and encourage him to try and enjoy trying different things.
He starts full time school in Sept and I know he will grow and change .
Until then I will stock up on the haliborange and malt extract I remember so well ( only joking)!
Searching for recipe in Supercook magazine