1. In a large heavy bottomed saucepan, combine beer, water, sugar, butter and salt.
2. Place the pan on a very low flame and heat the liquid without letting it boil or simmer.
3. Whisk the egg yolks until thick and pale then blend in the cream.
4. Add a little of the hot liquid to this and stir to mix well.
5. While whisking constantly, add the egg-cream mixture to the hot liquid in the saucepan.
6. Cook, stirring constantly, until it thickens.
7. Ladle the soup into warm soup bowls or cups and serve piping hot.