2 Step GR of Process Order

Our plant implemented a 2 step goods receipt process a few years back, where in house production of packed goods was changed from a simple COR6 goods receipt, to a two step receipt where the production line confirmed the process order using COR6 and then the warehouse receipted this into stock using MIGO and receipting stock in against the process order number.

Where is this change applied? I have looked at material master data and the BOM, but can't find where to select this option. I know the answer is very simple, however I have completely forgotten how this was done.