Is continuous Q&A acceptable form of communication?

Adi is a great fan of chicken and absolutely craves the grilled ones from KFC. So when he saw 2 juicy leftover thighs in the fridge, he wnet into an excited state to get them. I caught him trying to sneak some out of the fridge. So I stop him and ask him - what is it that you want?

Now Chicken and Fish are possibly things he has been eating every day for the last 7 years. And yet, he failed to say it. I took out the pieces and showed it to him - which only made him more agitated and he started to throw in words not remotely resembling chicken. He was getting really frustrated. I had to give him a big hint with the word "Chicken" for him to repeat the prompt.

Looks like we will need to institute a regimen by which Adi should be asked to say what he is eating, what is he holding in his hand, where is he going, what is he wearing and so on. We used to do his frequently but stopped maybe a year back thinking all this is done for him. Has not happened. I think there is need for continuous practice with Autistic children - either formally or informally - for them to retain what they learned. Learning is not for keeps here.

So we go again.....