1. Collect the juice and zest from the lemons.
2. Combine and beat the egg yolks and sugar in a mixing bowl until it thickens.
3. Stir in the lemon juice and zest. Pour the mixture into a double boiler and let it simmer for 10 minutes until it thickens. Let it stand until it cools down.
4. In another chilled mixing bowl, beat the egg whites and salt until stiff peaks form. Fold in the lemon mixture and let it chill for 2 hours.
5. In another chilled mixing bowl, beat the whipping cream until stiff peaks form. Fold the mixture into the lemon mixture and chill until serving.

Source: Food.com

Photo credit: Franklin Heijnen on Flickr