VANILLA ICE CREAM

5 egg yolks
2/3 cups sugar
1 cup half and half
2 tablespoons butter
1 cup whipping cream
2 teaspoons vanilla extract

Beat yolks and sugar until blended. Pour in top of double boiler. Stir in half and half. Cook and stir over boiling water until thickens. Set aside - stir in butter. While cooling on a rack, stir occasionally until room temperature. Stir in whipping cream and vanilla. Freeze according to manufacturers directions.