There are three schools of thought about making shortcakes. One, the biscuit school, insists that the dough be stiff enough to roll or at least shape with two hands. Another calls for a more liquid dough or rather a batter that can be dropped on the sheet pan with two spoons. A third uses sponge cake. The rolling and shaping method is shown here, but if you want a more batterlike mixture, add an additional ⅓ cup heavy cream and spoon the batter onto the sheet pan.