Food & Cooking Recipes Dessert & Treats Recipes Pie & Tarts Recipes Key Lime Tart 3.8 (154) 16 Reviews Can't find key limes? Traditional limes work, too. By Martha Stewart Martha Stewart Martha Stewart is a bestselling author, entrepreneur, and lifestyle expert who has taught millions of people through generations the joy of entertaining, cooking, gardening, collecting, crafting, and home renovating via her eponymous magazine, Martha Stewart Living, Emmy-winning television shows, and 99 books (and counting). Based in Katonah, N.Y., where she helms her 156-acre Bedford Farm, Martha is America's first self-made female billionaire. Editorial Guidelines Updated on March 29, 2024 Rate PRINT Share Prep Time: 30 mins Total Time: 3 hrs Servings: 8 Jump to recipe Looking for an easy make-ahead dessert? This key lime tart has a simple graham cracker crust, which means there's no pastry to roll out, and all it requires is a quick whizz in the food processor before pressing into the tart pan. The filling is also super easy: simply whisk the condensed milk, sugar, and fresh lime juice together, pour it into the crust and bake, cool, and refrigerate. The buttery crust complements the creamy yet zesty filling. It’s a perfect dessert any time of the year, but we especially love its cool creaminess in the summer. Key Lime Pie Credit: Rachel Marek Why We Love This Key Lime Tart So Much This easy dessert recipe has a lot to recommend it: Easy and foolproof: Both of the components for this tart are beyond easy. The crust is blitzed in the food processor and baked until golden and fragrant—no making pastry or rolling dough necessary. All the ingredients for the filling are simply whisked together and poured into the baked crust. From there, the tart takes another spin in the oven until the filling is set. Can be made ahead of time: This tart needs some time (at least two hours) in the refrigerator to fully set, so it should be made ahead. You can make the tart one day in advance—just cover the top loosely with plastic wrap to prevent a skin from forming on top of the filling. After more than one day, the crust will start to become a bit soggy, but the tart will still be delicious.Perfect crust-to-filling ratio: Whether we’re talking about pies or tarts, everyone loves a good crust. The creamy lime filling in this recipe bakes on top of a thick layer of buttery graham cracker crust. It’s a roughly 3:1 ratio of filling to crust, which is ideal. Neither component will overpower the other, and they complement one another perfectly. Sweet and tart: The graham cracker crust is sweet and buttery, and the filling is both sweet and tart. Granulated sugar and sweetened condensed milk add plenty of sweetness, and a generous amount of fresh lime juice brings an acidic punch that balances out the sweetness. How to Check the Filling Is Properly Cooked: Carefully and gently jiggle the pan. If about 2 inches of the outer part of the tart is fully set and the center part is still a little wobbly, it's cooked and you should pull the tart from the oven. Making a Graham Cracker Crust A graham cracker crust is probably the easiest tart crust of all. You can buy a pre-made one at the store, but a homemade one will taste better and come together in just a few minutes. It only takes three ingredients—graham crackers, granulated sugar, and melted butter. Use the food processor to finely grind them and the crust mixture will be evenly moistened and ready to use. All you have to do is press it into an even layer over the bottom and up the sides of the tart pan. Using something with a flat surface, such as a drinking glass or dry measuring cup, to press down on the crumbs will help make the crust as even as possible. You’ll know the crust is baked when the graham cracker crumbs take on a lightly tanned color and it smells fragrant and buttery when you open the oven door. If you don’t have a food processor, buy graham cracker crumbs instead of whole crackers. If you start with crumbs, you can use a fork to stir in the sugar and melted butter. Nine to 10 whole graham crackers will yield about 1 1/2 cups of crumbs. Key Lime Tart Upgrades Graham cracker crust is a classic when it comes to key lime tart. It’s buttery and delicious and pairs perfectly with the zesty lime filling, but if you want to switch things up, you can swap the graham crackers for others, such as Biscoff cookies or vanilla wafers. You can also amp up the flavor of the crust by incorporating some warming spices. A dash of cinnamon, nutmeg, or five-spice powder will add some flair. Since you’re making a curd-type mixture for the filling, we don’t like to mess around too much with the ingredient ratios. However, other citrus can be substituted for the lime—lemon and grapefruit are both great options. In terms of garnish, this recipe keeps it simple by grating some lime zest over the top. You could take it one step further and use candied lime peel, or pipe on a few dollops of lightly sweetened whipped cream. Cook Mode (Keep screen awake) Ingredients 9 to 10 graham crackers (each 2 1/2 by 5 inches) 2 tablespoons plus ½ cup sugar 4 tablespoons unsalted butter, melted 1 can (14 ounces) sweetened condensed milk ¾ cup fresh lime juice (from 4 to 6 limes), or fresh or bottled key-lime juice 4 large egg yolks Pinch salt Slivered lime zest, for garnish (optional) Directions Credit: Rachel Marek Preheat oven and make cracker crumbs: Preheat oven to 350°F. Process graham crackers and 2 tablespoons sugar in a food processor until fine crumbs form. Credit: Rachel Marek Add butter and process: Add butter. Process until combined. Credit: Rachel Marek Form crust in tart pan and bake: Transfer mixture to a 9-inch tart pan with a removable bottom; pat into bottom and up sides. Place pan on a baking sheet, and bake until crust is fragrant and slightly colored, about 10 minutes. Credit: Rachel Marek Make filling: Meanwhile, in a medium bowl, combine condensed milk, lime juice, egg yolks, remaining 1/2 cup sugar, and salt; whisk until smooth. Credit: Rachel Marek Pour filling into crust and bake: Pour mixture into crust (warm or cool is fine), leaving 1/8 inch at the top; return to oven. Bake until filling is set around edge but still slightly loose in center, 20 to 25 minutes. Credit: Rachel Marek Cool then refrigerate: Cool completely at room temperature; then refrigerate until chilled, at least 2 hours. Serve, garnished with lime zest and whipped cream, if desired. Credit: Rachel Marek Storage Instructions If you plan to make this key lime tart the day before serving it, we recommend laying a piece of plastic wrap loosely on top to cover the filling. When creamy fillings like this are left exposed, they tend to develop an unpleasant film on top. The filling is so creamy that there’s no need to let the tart rest at room temperature–simply remove it from the refrigerator and serve it straight away. Frequently Asked Questions What's the difference between key lime and lemon meringue pie? The difference between key lime and lemon meringue pie (aside from the obvious lime vs. lemon) is in the crust and filling. Key lime pie is usually made with graham cracker crust; lemon meringue is made with traditional pie crust like pâte brisée. Key lime pie filling is made using sweetened condensed milk and eggs; lemon meringue filling is usually made on the stovetop with cooked eggs. And of course, lemon meringue pie is topped with swoops of sweet meringue; key lime tarts can be topped with whipped cream or lime zest, or left as is with no toppings. Do I have to bake the crust? Baking the crust isn’t absolutely necessary, but since you’re already turning on the oven we do recommend it. If you want to skip this step, make the crust as instructed, then pop it in the freezer to firm up while you work on the filling. Can I use regular pie crust? Yes, you use regular pie crust for this recipe if you’d prefer a more traditional pie crust instead of a graham cracker one. Be sure to blind-bake the pastry crust so that it remains crisp and flaky under the weight of the lime filling. Can I freeze key lime tart? We don’t recommend freezing this key lime tart. Dairy (in this case, sweetened condensed milk) doesn’t do well in the freezer—the extreme cold can change the texture of the filling. 5 More Tart Recipes to Try: Lemon Curd Souffle Tart Peach and Blueberry Tart With Cream Cheese Filling Mango-Coconut Cream Tart Strawberry Tart Raspberry Mascarpone Tart Originally appeared: Everyday Food, April 2007 Rate PRINT Updated by Riley Wofford Riley Wofford Riley Wofford is a recipe developer, food stylist, and writer with over 15 years of experience and holds a Professional Culinary Arts diploma from the International Culinary Center. In addition to MarthaStewart.com, Riley's work can be found in TODAY.com, Delish, Food52, and Marley Spoon.