Grease and flour an 8inch cake pan (preferably a springform cheesecake pan). Preheat oven to 350F.
Cream the butter and sugar until light and fluffy, then beat in the eggs adding a little flour and beating well after every addition.
Stir in the coffee essence and mix thoroughly. Turn the mixture into the prepared pan and bake for 35-40 minutes until springy to the touch. Turn out and cool on a wire rack.
To make the Irish coffee syrup: put the coffee and sugar into a small pan and bring up to a boil stirring to dissolve the sugar. Then boil for 1 minute.
Remove from heat and add the whiskey. Wash and dry the pan the cake was baked in and return the cooled cake to it; then pour the hot coffee syrup all over it.
Leave in a cool place for several hours, then turn out. Whip the cream until its thick, sweeten slightly with confectioner’s sugar and add whiskey to taste.
Spread the cake with the whipped cream and chill for an hour before sprinkling with chopped nuts or grated chocolate.
