18 month old will not eat any meal I prepare myself

[Summerdays2014]

Breakfast is fine - porridge or weetabix and fruit.
Lunch and dinner however have become a battlefield over the last few weeks. He won't eat anything I cook. Beans on toast or cheese on toast or sausages is it. Happy to eat snacks eg breadsticks with cream cheese or hummus etc. This week I've done all his old favourites and tried new things. It's got to the point where he won't even eat potato or any of the veg or meat he used to eat. I tried being strict last week, giving one choice and nothing else. Stuck at it for 4 days but then stopped as I couldn't stand the constant screaming and he still wasn't eating.

He goes to nursery once a week and eats anything there apparently... at home he will eat loads of what he wants - breadsticks, toast, youghurt, fruit etc but in reluctant to give these now as snacks in case he's just filling up on them.
The only other things he will eat are Ella's kitchen pouches. One day in desperation I gave him one of those and he ate the whole lot. So that's what I give him when I'm desperate.
Not sure where to go from here?

Thanks.

My DS is 17 months and his daily diet is pretty much as follows:
190ml milk + 1 petit filous yogurt + about an 1/8 of a slice of toast (on a good day)
50ml milk + 50g baby food + 1 petit filous yogurt
150ml milk + 50g baby food + custard

I feel your pain in having a child that won't eat. DS is under a dietitian for other reasons and speech and language have assessed him but the best advice they gave me, and it's already been said on this thread, is that it's your job to provide food and it's their job to eat it. I do offer DS a wide range of foods but he never really wants it. I've not seen many teenagers asking their Mums for baby food so I'm reckoning he'll grow out of it ... until then Ella's Kitchen and jar foods are what he will eat.