Key Lime Tart

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.

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. 
  

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.

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.