The day before serving, make the batter. Mix the flour, sugar, salt, oil and egg yolks in a mixing bowl. Gradually stir in the beer. Refrigerate overnight. Also, the day before serving, coat the ice cream balls thoroughly with the crushed cornflakes. Place the ice cream balls in the coldest part of the freezer and freeze overnight. When ready to serve, heat the peanut oil, in a deep fat fryer or deep pot, to 190ºC . Beat the egg whites until stiff and fold into the batter. Coat 2 or three of the ice cream balls completely and heavily with the batter and add to the hot oil. Turn up the heat to maintain a temperature of 190ºC . Fry the ice cream until golden brown. Remove with a slotted spoon to paper towels, draining briefly. Serve immediately. Repeat with the remaining ice cream balls.