Banana Sour-Cream Pie

Put the sour cream into the top part of a double boiler and heat over boiling water until moderately hot. The cream will get thinner as it heats.

Beat the egg yolks lightly in a mixing bowl and stir in the sugar and cornstarch. Gradually add the hot sour cream, stirring vigorously. Cook over boiling water for fifteen to twenty minutes, until thick. Remov