I used to love Key lime pie so much that I'd order it any time I saw in on a menu. Unfortunately, my body turned against me once I hit 30, picking a fight whenever I ate dairy. But instead of giving up my favorite dessert, I was pretty sure I could make a lime pie with filling that was tangy, creamy, and sweet, encased in a crisp crust, one you'd be proud to serve at any party to vegans and non-vegans alike.
There's a lot of great pie information in the Serious Eats library, and I leaned on several recipes to come up with my own. From Stella Parks's lime pie recipe, I borrowed the idea of adding rosewater to give the lime flavor a bit of the freshness it loses during cooking. I also loved that Stella's investigation into the differences between Key limes and Persian limes, which sparked a controversy in Florida, essentially gave me permission to use the more commonly available Persian limes. (However, I still think of this as a Key lime pie, as that was the flavor profile I was trying to achieve.)
For the crust, I used Lauren Weisenthal's terrific recipe for Key lime pie as a starting point. My main worry was that vegan butter wouldn't be able to hold the graham cracker crust together as well as butter, but through successive trials, I finally got a crust with good structure by gradually increasing the amount.
For the meringue on top, I didn't have to do anything other than use Nik Sharma's perfect vegan meringue recipe.
With all that squared away, I just had to focus on getting the dairy- and egg-free filling just right. Sweetened condensed milk is a common ingredient in Key lime pie recipes, and swapping it out for dairy-free sweetened condensed coconut milk seemed straightforward enough; the coconut flavor isn't too strong, so it doesn't distract from the lime. I wanted to avoid using multiple nut products due to nut allergies, so I turned to silken tofu to partner with the coconut milk, which creates a creamy texture with some heft, and I turned to cornstarch to help thicken it up and get it to set. While I tried to engineer the recipe so you could fill the pie crust and bake it all together in order to reduce the number of dishes, the filling never quite set correctly, so I chose instead to heat the filling on the stovetop until it was sufficiently thickend and then pour it into the prepared crust. After chilling the pie, the custard sets beautifully and the lime flavor shines through, with a hint of a kind of Creamsicle taste because of the addition of vanilla extract.
For the Crust: Adjust oven rack to lower-middle position and preheat to 375°F (190°C). Combine graham crackers, sugar, and salt in a food processor bowl and pulse until reduced to fine crumbs, 18 to 22 pulses. Add the melted fat and pulse until fully moistened and resembling wet sand. Pause to scrape down sides of the bowl with a rubber spatula, if needed.
Scrape graham mixture into a 9-inch glass pie plate, spread into an even layer, then compress firmly with a flat-bottomed drinking glass or measuring cup; this will naturally push the crumbs up the sides of the pan. Press the glass around the pie plate to compress the crumbs along the sides to create a rim. Bake for 10 minutes or until the edges are golden brown. Set aside to cool.
For the Filling: Combine tofu, sweetened condensed milk, sugar, lime zest and juice, cornstarch, and salt in a blender jar or food processor bowl. Blend on medium-low speed until completely smooth. Transfer to a 3-quart stainless steel saucier and bring to a boil over medium heat, whisking constantly, about 8 minutes. Continue cooking and whisking until mixture has thickened, about 1 minute. Remove from heat and stir in vanilla extract and rosewater (if using). Pour filling into prepared crust.
Let pie filling cool to room temperature, about 1 hour. Cover and refrigerate until filling is chilled and fully set, at least 6 hours or up to overnight.
For the Topping: Prepare the vegan aquafaba meringue according to the directions in the recipe but omit cardamom; after reaching stiff peaks, mix in 1 teaspoon vanilla extract during the last step instead. Spread the “meringue” over the pie with an offset spatula, or place in a piping bag fitted with a large star tip and pipe decorative stars to cover the surface of the pie. Serve immediately.
Scale, 9-inch glass pie plate, flexible spatula, food processor, blender, 3-quart stainless steel saucier, whisk, instant-read thermometer, stand mixer, offset spatula, pastry bag and tips (optional).
Honey is a common ingredient in graham crackers, but it isn't considered vegan compliant. If you can’t find vegan graham crackers (look for brands such as Nabisco Original or Keebler Original), the recipe works equally well with Whole Foods Organic Vanilla Animal Cookies.
This recipe was tested with Let’s Do Organic Sweetened Condensed Coconut Milk; if using other brands, be sure to measure it out by weight, as they may be packaged in differently sized cans. Sweetened condensed coconut milk has a firm fat cap on the surface that needs to be gently broken through to reach the thinner contents underneath; empty the contents of the can over a bowl to catch any liquid that might squirt out.
Not all refined white sugar is considered vegan compliant, but organic cane sugar always is. This recipe was tested with both, and the difference was only apparent in the aquafaba meringue, which has a reduced shelf life when made with organic cane sugar, owing to its natural molasses content. For that reason, a pie topped with aquafaba meringue should be made and served on the same day. The pie, bare or topped with white sugar frosting, can last in the refrigerator for 3 days.
Read the notes sections of Stella Parks’s Fresh and Creamy Lime Pie Recipe for more information on prepping citrus ahead of time and nonreactive cookware.
Make-Ahead and Storage
The semi-prepared pie can be covered and refrigerated up to 3 days before preparing the topping. After topping with “meringue," it’s best served right away.