In the top of a double boiler or in a heavy-bottomed saucepan, beat egg yolks with sugar, salt, and sherry. Beat until smooth. Cook for 8 to 10 minutes or until sauce thickens, stirring constantly. Remove from heat and let cool completely. In the bowl of a mixer, whip cream until it holds peaks. When sauce has cooled completely, gently fold in whipped cream. Serve over chilled, drained pears for a quick and easy cool dessert.