2 1/2 cups graham cracker crumbs
1/4 cup dark brown sugar
1 stick melted butter
1 - 2 tablespoons egg whites, room temp
Baked Layer
2 14 oz cans sweetened condensed milk
1 cup key lime juice
8 egg yolks, room temp
1/2 cup sour cream, room temp
Chilled Layer
8 oz cream cheese, softened
1/2 cup sweetened condensed milk
1/4 cup key lime juice
1/4 cup sour cream, room temp
2 tablespoons granulated sugar
Whipped Layer
1 1/2 cups heavy cream, very cold
2 tablespoons sugar
2 tableponns key lime juice
Preheat oven to 350
Place parchment paper on the bottom of a 9" spring form pan. Set the ring on top of the parchment paper to close the seal. Trim the paper on the outside as close to the pan as you can. This will ensure that you can lift the pie off the bottom of the spring form pan. Wrap the outside of the spring form pan in aluminum foil to prevent any leakage during baking.
In a large bowl, combine the graham cracker crumbs and brown sugar. Add the melted butter and mix. Add the egg whites and mix again. Quickly cover the bottom of the spring form pan and up the sides, make sure the edge of the ring and the bottom where they come together is covered and press the bottom and sides with a glass to pack well. Move to the oven and bake for 15 minutes.
While the crust is baking add the egg yolks to a large glass bowl and whisk for one minute. Add the 2 cans of sweetened condensed milk to the mixture and whisk until well blended. Add the sour cream and whisk. All of this should be at room temp. Add the key lime juice and whisk. The mixture will begin to thicken, this is a reaction of the acid in the key lime juice and the sweetened condensed milk. There will be lots of air bubbles, this is okay. Pour the mixture into the crust that is coming out of the oven and spread evenly. Bake at 350 for 20 minutes. The baked layer will set up and be set all the way to the center. Cool completely before adding the chilled layer. Do not refrigerate until completely cooled or the crust will absorb moisture and separate.
To make the no bake chilled layer, cream the 8 ounces of cream cheese and 2 tablespoons of granulated sugar until fluffy. Add the room temp 1/4 cup sour cream. Mix well, add the 1/2 cup sweetened condensed milk and mix well again. Add the 1/4 cup of key lime juice and mix well.
Use a spatula to smooth over the baked and completely cooled layer, this should only come up to about 3/4 to the top. Chill in the refrigerator.
The final layer is the key lime whipped cream. Add the whipping cream to a clean and chilled bowl. Add sugar and whip to soft/medium peaks. Do not whip to stiff peaks. Begin adding the key lime juice, this will cause the mixture to thicken. Add the key lime juice a little at a time to get the consistency you prefer. Spread over the pie and chill for several hours before serving.
