Cereal: beat the butter, sugar & vanilla together until light and fluffy. About 3 minutes.
Add the egg and beat again.
Meanwhile whisk together the dry ingredients and add this to the mixer until just combined.
Fold in the chocolate chips.
Split the dough in two and place each on a piece of baking paper. Roll the dough into a log about 1” wide. Chill in the fridge for 20m.
Slice the log up into small circles about ½” thick, then bake on a lined tray for 5-6m at 175C. Allow to cool once cooked.
Ice Cream Cake: place the cookie crisp cereal in a food processor and blitz to a fine crumb. Add the melted butter and stir together until you have a mixture that has the consistency of slightly wet sand.
Place 1/2 of the crumbs into the base of 7” springform cake pan.
Spread half of the softened ice cream on top of the crumb base, then drizzle over chocolate sauce and the remaining cookie crumbs.
Top with more ice cream and place the entire cake in the freezer overnight.
Assembly: remove the cake from the freezer and whip the cream, sugar and vanilla to soft peaks.
Drizzle some chocolate sauce in a zig zag over the top of the cake and then using a french tip nozzle, pipe even dollops of cream around the outside.
