Originally Posted by Jagboi

I always put the cream on first. There are solid technical reasons to do this, because of the viscosity and coeffecients of friction of the two fluids and surface interfaces. It's easier to spread cream (especially if it's cold) on a scone, than it is to spread it on jam. Unless one wants to make an emulsion of the jam and cream and then spread the resultant mixture. Although that wouldn't work well if the jam has pieces of fruit rather than being made with fruit puree; it's more desirable to have a homogeneous mixture for spreading on the scone.