This decadent Key Lime Cheesecake recipe features a creamy, citrus-bright filling, a buttery graham cracker crust, and a fluffy homemade whipped cream topping for the ultimate refreshing dessert.
Cover the bottom and sides of a 9-inch springform pan with extra-large aluminum foil so that no water can leak in (it's worth a trip to the store to buy the 18" wide foil). Wrap it with two layers for extra security. Crimp the top of the foil around the top edge of the springform pan. You can also place the unwrapped springform pan in a slightly larger cake pan (10") that has 2" sides (I ran out of big foil but had a nice cake pan that it just barely fit into. I didn't have to worry at all about the foil keeping water out).
Preheat oven to 350°F (175°C), placing the top rack in the lower third of the oven. In a large mixing bowl, mix together the finely ground graham cracker crumbs with the sugar and salt. Pour the melted butter over top and mix until the crumbs become coated.
Pour into the prepared springform pan and gently smooth out (I like to use a metal measuring cup for this). Carefully work the crumbs up the sides so that they are 1½" tall and approximately ¼" thick. You should have a nice layer on the bottom and the sides should go about halfway up your pan. Place into the oven and bake for 8-10 minutes or until lightly golden brown. Turn the oven down to 325°F (160°C).
Beat the cream cheese, salt, vanilla, and lime zest in the bowl of a stand mixer fitted with the paddle attachment for approximately 4 minutes or until smooth and creamy. With the mixing speed on low, gradually add the sugar mixture, then turn it back up to high and beat for an additional minute. With the mixing speed on low, add the eggs one at a time, mixing until incorporated. Add the lime juice and sour cream, then the heavy cream, and beat on high for 1 minute.
Place the prepared springform pan into a large high-sided roasting pan. Pour the cream cheese filling into the springform pan, smoothing out the top with a spatula. Pour boiling water around the springform pan, taking care not to get any on the filling. You'll want the water to go halfway up the side of the pan (this was just to the lip of my 2" tall cake pan). Place in the oven and bake at 325°F (160°C) for 1 hour and 45 minutes. If you like extra firm cheesecake, continue baking for an additional 15 minutes for a total of 2 hours. If the cheesecake is getting too dark, tent it with foil (taking care not to let it touch the top of the cheesecake).
After the cheesecake has been baked, turn off the oven, slightly crack the door open, and allow it to cool for 1 hour. This is the key to getting a perfect top without it falling or cracks forming. Remove the cheesecake from the bath, dry the bottom, and cover with foil. Place in the refrigerator to chill for at least 4 hours before serving; I prefer 6+ hours.
Prepare the whipped cream by beating all of the ingredients in the bowl of a stand mixer fitted with the whisk attachment until stiff peaks form. Using an extra-large star tip, pipe over the top of the cooled cheesecake (you can also do this at about 3 hours into the chill time so that it can firm up even more during that remaining hour). During the chilling process, the cheesecake should come away from the edges of the pan, making it easy and mess-free to remove before serving. Garnish with graham cracker crumbs, lime zest, and lime slices, if desired.
Notes
*You can also use 1/3 c. lime juice + 1 tbsp. lemon juice.STORE your Key Lime Cheesecake in the refrigerator, covered with plastic wrap or in an airtight container, for up to 5 days.To FREEZE, let the cheesecake cool completely, wrap it tightly in two layers of plastic wrap and a layer of tinfoil, and place it in an airtight container (bag or Tupperware). It will stay good in the freezer for up to 3 months. To serve, thaw in the refrigerator overnight, then add the topping and garnishes before serving.