Creamy Chocolate Frosting

1/2 c. butter
1 3/4 c. powdered sugar
1/2 c. cocoa
2 unbeaten egg yolks
1/4 t. salt
1 t. vanilla
3 T. milk

Cream together butter, sugar and cocoa. Add egg yolks and salt and blend thoroughly. Add vanilla and milk. Spread on cooled cake

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