Grate the zest of two oranges and set aside. Squeeze the juice and put into a shallow dish. Cut 4–5 balls of stem ginger
(the sort you buy in syrup) into small chunks and set aside. Whip 300 ml double cream until it forms stiff peaks.
Beat 250g mascarpone until soft, mix in 4 Tbs of the syrup from the stem ginger and fold this into the beaten cream,
together with the ginger chunks and the grated orange zest. Spread a third of this into a dish. Cover this with a layer
of savoiardi (boudoir) biscuits dipped for a few seconds in the orange juice. Spread another third of the cream/mascarpone
mixture over this, then cover with another layer of orange juice-dipped savoiardi biscuits. Finally, spread the remaining
cream/mascarpone over the top, and chill for several hours in the refrigerator. Take out of the refrigerator an hour before
serving, and cover the top with grated chocolate. (Note: for a boozy version of this, you could add some sweet sherry
to the orange juice for dipping the biscuits!)