Recipe from allrecipes.com
5 egg yolks, beaten
1 (14 oz) can sweetened condensed milk
1/2 cup key lime juice
1 (9 inch) prepared graham cracker crust
Preheat oven to 375.
Combine the egg yolks, sweetened condensed milk and the lime juice. Mix well. Pour into unbaked graham cracker shell.
Bake for 15 minutes. Allow to cool. Top with whipped topping and garnish with lime slices if desired.