Inspired by my new summer novel, The Best Is Yet to Come, these Key Lime Pie Bars are the perfect combination of creamy, tangy filling, buttery graham cracker crust, and lightly sweetened whipped cream. There is very little difference between Key limes and regular limes, so we use regular ones here. We highly recommend squeezing your own juice for these bars, as the bottled lime juice doesn’t taste as fresh.In a large bowl, mix together the graham cracker crumbs, butter, brown sugar and salt until all of the liquid is absorbed. Press into the bottom and a little up the sides of the pan. Bake for 10 minutes, until lightly golden brown and fragrant.Whisk all of the filling ingredients together in a large bowl, then pour over hot crust. Bake at 350°F for about 15 minutes, until set.In a large bowl, whip cream and powdered sugar until soft peaks form. Spread on top of the cooled filling.Sprinkle with lime zest. Cut into 9 squares, arrange a few lime slices on top and serve.

Key Lime Pie Bars
Makes 9

Crust:
12 graham crackers, finely crushed (about 1 ½ cups)
6 tablespoons unsalted butter, melted
1/3 cup brown sugar
¼ teaspoon kosher salt

Filling:
14-ounce can sweetened condensed milk
1 tablespoon lime zest
½ cup freshly squeezed lime juice (from about 4 limes)
¼ cup sour cream
1 egg yolk

Topping:
1 cup heavy whipping cream
¼ cup powdered sugar

1 Tablespoon lime zest (from 1 lime), for garnish
Thinly sliced limes, for garnish

Preheat oven to 375°F. Line an 8×8-inch baking pan with foil and spray with nonstick baking spray.

In a large bowl, mix together the graham cracker crumbs, butter, brown sugar and salt until all of the liquid is absorbed. Press into the bottom and a little up the sides of the pan. Bake for 10 minutes, until lightly golden brown and fragrant. Turn heat down to 350°F.

Whisk all of the filling ingredients together in a large bowl, then pour over hot crust. Bake at 350°F for about 15 minutes, until set. Transfer to a cooling rack and cool for 1 hour. Transfer to the refrigerator for at least 1 hour until completely cooled.

In a large bowl, whip cream and powdered sugar until soft peaks form. Spread on top of the cooled filling. Sprinkle with lime zest. Cut into 9 squares and serve. (Can be made ahead and refrigerated up to two days before serving.)