Whip all ingredients to stiff peaks. Set aside until making the pudding
Mix sugar, flour and salt in a large heavy saucepan. Gradually stir in the scalded milk with a whisk. Cook the mixture over moderate heat while stirring constantly until slightly thickened. Slowly stir in approximately 1/4 cup the hot mixture into the beaten egg yolks. Next add the yolks to the balance of the hot mixture and cook, stirring constantly until the mixture is fully thickened to a custard-like consistency and coats a spoon. Remove from heat and stir in the vanilla. Let cool completely and then fold in 1/2 cup of the whipped cream. Use a large crystal bowl (or a trifle bowl) and spread a little of the custard on the bottom. Alternately layer banana slices and vanilla wafers, reserving 4 wafers, with custard in between each. Repeat and end with vanilla wafers on top. Spread remaining whipped cream over the top. Grind the 4 reserved wafers coarsely and mix with the ground macadamia nuts. Sprinkle on top of the whipped cream. Garnish with a fresh sprig of mint. Chill at least 30 minutes and serve.