Instructions For the brownies: Follow the instructions on the back of your brownie mix for mixing your brownie together. Replace all the water with rum and add espresso powder. Bake the brownies in a greased 9 x 13 inch pan according to package directions. Remove and allow to cool.
Combine egg yolks, rum, and sugar in a double boiler (or heat proof bowl set inside a pot of simmering water).
Cook, whisking constantly, until egg mixture is smooth and turns a pale yellow color. This will take about 5-7 minutes. Remove from heat. Stir in mascarpone cheese.
In the bowl of an electric mixer or other large mixing bowl, beat cream until soft peaks form. Stir cream into the mascarpone mixture.
The mixture will deflate a little bit. At this stage I divided the mixture into 2 and added brewed coffee to half of the mixture.
Whisk together the coffee and rum in a deep bowl. Break the brownie up into bite sized pieces. Dip the brownie into the coffee mixture for just a second or two then place it in the serving glass of your choice.
Follow that with a good scoop of the mascarpone mixture followed by the one with coffee and then more brownie. Repeat, ending with a layer of cream. if desired. Between any of the layers you can add some diced kiwi ( I did just to break the monotony of colours)
Serve chilled .