Key Lime Pie

4 egg yolks
1/2 c key lime juice
1 (14 oz.) can sweetened condensed milk
1 (9 inch) graham cracker crust -
4 drops green food coloring
Cool Whip

Beat yolks; add lime juice while beating. Add sweetened condensed milk, continuing to beat. Add food coloring and mix thoroughly. Pour into crust and bake in preheated oven at 350* for 15 minutes. Cool completely, then top with Cool Whip for serving.

Thanks, MOM!!!!