In the top of a double boiler (no heat yet), mix together the dark beer, 1/2 cup of the water, white granulated sugar and freshly squeezed lemon juice.

Sprinkle the gelatin over the remaining cup of water and mix it in until dissolved.

Add the gelatin water to the sugared dark beer mixture. Stir to combine

Beat the egg yolks together slightly and stir them slowly into the beer mixture.

Heat water in the lower part of the double boiler until simmering and place the top part with the beer mixture in it over the simmering water.

Cook about 8 minutes stirring constantly until the mixture thickens a bit enough to coat the back of a wooden spoon.

Remove the mixture from heat, cool completely.

Beat the egg whites until they form stiff peaks.

Fold the egg whites into the sweet beer mixture, making sure they are thoroughly combined.

Before serving. Whip the heavy cream and the tablespoon of powdered sugar together until stiff.