1/4 c. butter, melted
1 1/4 c. graham cracker crumbs
1/4 c. sugar
3 egg yolks
1 (14 oz.) can Eagle Brand sweetened condensed milk (not evaporated milk)
1/2 c. ReaLemon lemon juice from concentrate
Few drops yellow food coloring (optional)
Cool Whip

Combine butter, crumbs and sugar; press into 8 or 9 inch square pan. In bowl, beat egg yolks; stir in sweetened condensed milk then ReaLemon and food coloring, if desired. Pour into crust. Top with Cool Whip. Freeze until firm.