Just notice that you only mention dinner foods. What does he eat for breakfast and lunch ? You can play with breakfast foods as well. Beautiful fresh fruits in yoghurt with a healthy granola or so. Or pancakes baked with blended sweet potato and instead of plain flour use chick pea or lentil flour (adding more veggies).

That what he eat is quite healthy. You could try and add more different veggies to the chili con carne. Some finely cut nearly invisible veggies to the noodles, homemade ice cream / blocks with fresh fruits, etc

Wow they are weird foods for a 4.5 year old to like. ? Seems like he likes hot and spicy?

When I introduced soups my kids really loved pumpkin soup I added some sweet potato in it.

Try adding extra veggies and fruit to other dishes you make that he likes, (if you want to hide them, (from him) that’s fine). Bolognese sauce is great for adding different veggies to. Also try him with fritters and pikelets that contain veggies, pumpkin pikelets are so yumm. And don’t forget the special treats, chocolate cake with beetroot is delicious and the good old carrot cake with banana. And if this is not working you may resort to special milk dietary drinks for added nutrients.
Best of luck and all the best of wishes to you and your little master.

What ever he loves that is healthy just let him eat it!

I would grate veggies into dishes ie. carrot and zucchini into spag bol. It is hidden but holds a lot of flavour when you cook. Get your little one to help – tell them they need to have 3 veggies in their meal and let them pick which ones. I find if the child has involvement, they are more likely to participate. And praising them for tasting a vegie they really dislike helps.
I cook up potato, pumpkin, swede, carrot and mash it and add a bit of butter and a teaspoon or two of Vegemite. Sounds so wrong, but it tastes good.