With an electric hand beater, whip together the cream and icing sugar until smooth and firm.
Fold in the mascarpone. Fit a piping bag with a 2A nozzle and fill it with the cream.
Ganache
Heat the cream and add the chocolate into it. Stand for 5 minutes until the chocolate is soft, then stir until smooth.
Layers
#1 - 4 Oreo cookies {plus one small one for the centre, optional}#2 - 15ml Kahlua {or a shot of coffee}#3 - Pipe half the mascarpone cream over the soaked biscuits.#4 - Pour the ganache over the cream layer and place it in freezer for 10-15 minutes until it firms up. #5 - Top the ganache with 4 Oreo cookies {plus one small one for the centre, optional}#6 - 15ml Kahlua {or a shot of coffee}#7 - Pipe the remaining cream over the biscuit layer and level off.
To finish
Dust with cocoa powder and top with an Oreo cookie.