Lemon Sour Pie

1 graham cracker pie crust
1-1/4 c. sugar
1/2 c. cornstarch
1/4 tsp. salt
1-3/4 c. water
4 egg yolks
1 T. butter or margarine
2 tsp. finely grated lemon peel
1/4 c. lemon juice
3 drops yellow food coloring
1/2 c. sour cream


In saucepan, combine sugar, cornstarch, and salt. Beat water and egg yolks until blended. Add to sugar mixture. Stir constantly over medium heat until thick and boiling. Boil 1 minute. Remove from heat. Add butter, lemon, lemon juice, and food coloring. Stir until butter is melted. Stir in sour cream, blending until smooth. Pour into crust. Chill for 2 to 3 hours.