Key Lime Cheesecake with Key Lime Custard

One of my chicas from work walked in with a huge bag full of what she called 'Mexican limes' (a.k.a. key limes). I'm not talking about one of those plastic bags from the grocery store. I'm talking about a huge thick plastic bag. I have no idea how many pounds it was (multiple) but I do know that I ended up with more than 6 cups of juice!

Her request? "Can you make a key lime cheesecake?"

I'm thinking....Ummm...sure. But I've never even tasted, let alone made a key lime pie. How will I know if it ends up right? I have nothing to compare it with.

There begins the challenge. I searched through several recipes. Read numerous reviews. Omitted any recipe that called for flour. Is that weird? I've just never made a cheesecake with flour. I don't understand why it would even be required. In my mind, something isn't right. Am I being a cheesecake snob? Do I need to be enlightened here? Please fill me in if I'm being ignorant about this.

Anyways....I came across a recipe that not only had a good solid cheesecake recipe, but included a delicious surprise inside.......

Key Lime Custard!! Yes, there is a layer of amazing key lime custard underneath all that cream cheese deliciousness.

There's also a layer of sour cream on top. In the reviews, several people whined about it. How it's not needed. They didn't understand why it was even in the recipe. I personally add this particular layer to just about every cheesecake I make. If it's not your thing...by all means, don't worry about it. just leave it off and bake the cheesecake an extra 10 minutes.

Key Lime Cheesecake with Key Lime Custard

Inspired by: Key Lime Cheesecake
Serves 10-12

Key Lime Custard
6 large egg yolks
3/4 cup sugar
6 TB key lime juice
1 tsp key lime zest

Crust
1 3/4 cups graham cracker crumbs
1/4 cup sugar
1/2 cup melted butter

Filling
2 - 8oz packs of cream cheese, room temperature
2/3 cup plus 3 TB sugar, divided
2 large eggs
3 TB key lime juice
1 TB key lime zest, plus more to garnish if desired
16 oz sour cream
Thin key lime slices to garnish

Key lime custard:
In a heavy sauce pan, over medium heat, whisk together all of the custard ingredients. Continue whisking until it boils and let boil, while whisking, for 30 seconds. This will take about 8 or 9 minutes.

I cannot stress enough how important it is to whisk! Not stir. Whisk!! You do not want the egg yolks to scramble. Scrambled custard would just be nasty.

Cool to room temperature, stirring occasionally, keeping in mind that it will thicken more as it cools. Set aside.

Crust:
Preheat the oven to 350'

Wrap the outside of a 8' or 9" springform pan with 3 layers of aluminum foil. You need the foil to go up the sides about 3".

In a medium bowl, combine the graham cracker crumbs and sugar. Stir in the melted butter until well combined.

Press the mixture inside your prepared springform pan, and up the sides about 2 inches.

Bake for about 5 minutes and allow to cool completely.

Filling:
Cream the cheese and 2/3 cup of sugar until almost smooth (don't stress about the lumps. They'll go away while baking). Mix in the key lime juice and zest. Add the eggs one at a time and blend until just combined. Don't over blend. You don't want air bubbles in your cheesecake. Air bubbles help create cracks.

Assembly and Baking:
Spoon the custard into your crust, making it as even as possible and smooth it over.

Spoon the filling over the custard, carefully.

Using a roasting pan that's big enough to hold the springform pan, place the springform pan into the roasting pan. Pour enough water in the roasting pan so that the water comes 1" up the sides of the springform pan.

In your already 350' heated oven, bake for about 45 minutes, or until just set. Just set means that it's still a slightly jiggly and the center is not all puffy.

While the cheesecake is baking, in a medium bowl, mix together the sour cream and 3 tablespoons of sugar.

When the 45 minutes is up, spoon the sour cream mixture over the top and bake for an additional 10 minutes.

Place on a cooling rack and let cool for about 10 minutes. Remove the foil and remove the springform pan siding. If needed, run a knife around the edge. Let cool completely then cover and refrigerate over night, allowing it to completely set.

Garnish with lime slices and zest if desired.

It is tart and sweet and absolutely delicious!

This was the first time I had done the whole foil with the pan in water thing. I almost didn't. I typically just place a pan of water on the rack below which creates steam and helps with the whole cracking thing. But because of the custard, I chose to do as I'm told. It worked and the 'mmmm' sound that came from my chica's as she ate it, told me that it was a success.

Thank you for the key limes, Nancy!