This easy Key Lime Pie from scratch has only 3 ingredients in the satiny smooth filling. Because the filling doesn't contain eggs, there's no need to bake it, giving it an awesome texture and retaining the taste of fresh limes.
Growing up in California, Key Lime Pies were one of those unappealing slime green insta-desserts involving Cool Whip and Jello, that were so popular during the 80’s. I never got the appeal, until I took a trip to the Florida Keys in the summer of 2009. It was there, at a nondescript shack along the Oversea Highway, that I had my first taste of a real Key Lime Pie. I was there for the fried conch, but the pie in the case is what drew my appetite and I was soon devouring my first slice of many delicious Key Lime Pies, as I ate my way around the Keys.
I’ve tried making Key Lime Pie a number of times since then, but I’ve never been able to do that taste memory justice. Traditional Key Lime Pies are made with sweetened condensed milk, egg yolks, and lime juice, but because eating uncooked eggs is unwise, most recipes these days call for them to be baked in the oven. This not only renders the custard much firmer, the heat takes the fresh edge off of the lime juice.
I wanted to come up with a Key Lime Pie that doesn’t require the filling to be baked. The breakthrough moment came when I made a yuzu posset a few months ago. A posset is an eggless custard that’s set through a chemical reaction between boiled cream and citrus juice. The first thought I had when I tasted it was that I’d found my solution for making a delicious Key Lime Pie that you don’t need to worry about eating. The best part is that this method makes it ridiculously simple to make the pie. The filling consists of only 3 ingredients, and comes together in under 10 minutes.
To ensure I got as much lime flavor into the filling as possible, I add both lime juice and lime zest, but I strain the zest out before filling the pie shell in order to keep the texture of the filling nice and smooth.
With a buttery graham cracker crust and a cool silky filling that melts on contact with your tongue into a tangy pool of fresh lime flavor, this pie brought back delicious memories from my trip to the Keys. The rich milky sweetness from the cream mellows the harsh acidity of the limes, and the temperature sensitive filling sets firm in the fridge but melts like a ganache in your mouth, giving it an indescribably smooth texture.
- Move your oven rack to the middle position and preheat to 325 degrees F (160 C).
- Crumble the graham crackers into the bowl of a food processor and add 3 tablespoons of sugar. Pulse until they're fine crumbs (but not so long they turn into powder).
- Add the melted butter and pulse until combined.
- Dump the mixture into a pie plate and press the crumbs into an even layer along the bottom and up the sides of the pie plate. Using a heavy flat-bottomed object such as a glass helps ensure the bottom is packed tightly.
- Bake the crust in the preheated oven until fragrant (about 15 minutes). Remove from the oven and place on a cooling rack.
- Add the heavy cream and sugar to a pot and bring to a boil. Lower the heat and cook, stirring constantly for 5 minutes.
Turn off the heat and stir in the lime zest and lime juice.
Let the mixture cool to room temperature, and then strain it into the pie crust through a sieve to remove the lime zest. Cover the key lime pie and refrigerate until the custard is fully set (2-3 hours).
- Whip the whipping cream until soft mounds form, Add the powdered sugar and vanilla. Continue whipping until the cream forms well defined peaks, but not until it's hard.
- Add the cream a piping bag fitted with your favorite tip and pipe the cream onto the pie. You can also just mound the cream onto the pie.
I know some of you are looking at the ingredients list and thinking that it's not a key lime pie if it doesn't include key limes, but I'd be willing to wager you couldn't tell the difference between a pie made with the juice and zest of regular limes vs key limes. If you're not convinced, feel free to substitute key lime juice and zest.