Key Lime IceBox Cake (1958 Borden's Eagle Brand Condensed Milk Ad)

Key Lime IceBox Cake
(1958 Borden's Eagle Brand Condensed Milk Ad)

1 cup fine graham cracker crumbs
3 tbsp butter, melted
2 eggs, separated
1 (15 oz) can Eagle Brand Sweetened Condensed Milk
1/2 cup fresh lime juice and 1 tsp. grated lime rind OR 1 (6 oz) can fresh-frozen limeade
1/4 tsp. vanilla extract
1/4 cup sugar
3 to 4 drops green pure food coloring (if desired)

Combine crumbs and butter. Reserve 1/4 cup mixture. Press remaining mixture on bottom and sides of lightly buttered refrigerator tray, chill.   Beat egg yolks until thick, combine with Eagle Brand Sweetened Condensed Milk.

Add lime juice or limeade, rind and vanilla, stir until mixture thickens.  If desired, tint pale green.

Beat egg whites into soft peaks, gradually add sugar, beat until stiff but not dry. Fold into Eagle Brand-lime mixture. Pour into tray.

Border with reserved crumbs, decorate with slices of lime rind. Freeze until firm 4-6 hours.