Food & Cooking Recipes Dessert & Treats Recipes Pie & Tarts Recipes Key-Lime Mousse Pie Be the first to rate & review! By Sarah Carey Sarah Carey Website Sarah is the editorial director of food for Martha Stewart Living. Editorial Guidelines Updated on July 14, 2022 Print Rate It Share Share Tweet Pin Email Photo: Christopher Testani Prep Time: 35 mins Total Time: 3 hrs 10 mins Yield: 8 to 10 Serves Our modern take on Key-lime pie has a filling of whipped cream folded into a curd made with lime juice, sweetened condensed milk, eggs, and white chocolate—and tastes like a tart Creamsicle. It goes into a baked crust of crushed spice cookies (we used Biscoffs, but graham crackers are just as good), gets a shower of lime zest, and chills in the fridge. The winning result is both dense and airy—and, despite its swoopy looks, slices like a dream. Ingredients 7 ounces spice cookies, such as Biscoff (about 28) or Anna's (about 45), or graham crackers 5 tablespoons unsalted butter, melted 3 tablespoons sugar 1 large egg plus 2 large yolks ½ cup sweetened condensed milk ⅔ cup fresh lime juice, plus strips of zest for serving 3 ounces white chocolate, chopped (⅔ cup) 1 ¼ cups heavy cream Directions Preheat oven to 350°F. Blend cookies in a food processor until finely ground (you should have about 1 1/2 cups). Add sugar and butter; pulse until crumbs are evenly moistened. Press evenly into bottom and up sides of a 9-inch round fluted tart pan with a removable bottom. Refrigerate 15 minutes. Bake until fragrant and slightly darker brown, about 10 minutes. Let cool completely. Meanwhile, in a small saucepan, whisk together egg, yolk, and condensed milk, then whisk in lime juice. Place over medium-high heat and bring to a simmer. Cook, whisking constantly, 1 minute. Remove from heat and whisk in chocolate until melted. Transfer to a large bowl; let cool completely. Whisk cream to soft peaks. Whisk thoroughly into cooled lime mixture until smooth. (It may look slightly curdled at first, but keep whisking!) Spoon into a swoopy layer in crust. Refrigerate until set, at least 2 hours or, lightly covered, up to 12 hours. Serve, sprinkled with lime zest. Cook's Notes If you can't find Key limes, swap in juicy, thin-skinned Persian (regular) limes, or regular or Meyer lemons. Rate it Print