Stock control cascading options

Example
TShirts. we have 2 diffterent options (Color Grey & Blue) and we have various sizes (S M L XL XXL)
We have various stock availability of these.
I have created the item, with two Options (colour & Size) but i cant see how i can set the stock qty for the combo, eg grey/small= 9, Blue/Small 8
i can set a qty for blues and grey's and i can also set a qty for the size options, but i need it to take into account the colour and size.

My only thought is to remove the two options and combine to a single option list.
Current stock


Any ideas?

Hello Andrew,

You are right. The only solution for you in this case is use only one option "Size & Color", then you can implement what you want.

Sincerely, Giang