- 1 1/2 sticks cold unsalted butter, cut into 1/2-inch dice
- 1 1/2 cups all-purpose flour
- 1/3 cup granulated sugar
- 1/2 teaspoon flaky sea salt, such as Maldon
- 1 1/2 sticks unsalted butter, softened
- 1/2 cup honey
- 1/2 cup light brown sugar
- 1/4 cup dark brown sugar
- 1 teaspoon kosher salt
- 1 teaspoon flaky sea salt
- 1 teaspoon pure vanilla extract
- 1/2 cup heavy cream
- 1 cup walnut halves plus 1 cup coarsely chopped walnuts
How to make this recipe
Make the shortbread
Preheat the oven to 350°. Line a 9-by-13-inch pan with parchment paper, allowing 1 inch of overhang on the long sides. In the bowl of a stand mixer fitted with the paddle, mix the butter with the flour, sugar and salt at medium speed until a crumbly dough forms, about 6 minutes. Press the dough into the bottom of the prepared pan in an even layer. Refrigerate for 20 minutes.
Bake the shortbread for 25 minutes, until golden brown; rotate the pan from front to back halfway through baking. Transfer to a rack and let cool completely.
Meanwhile, make the walnut caramel
In a medium saucepan, melt the butter over moderate heat. Whisk in the honey, both sugars and salts and the vanilla. Cook, stirring occasionally, until the caramel reaches 220° on a candy thermometer, 2 to 3 minutes. Carefully add the cream and cook until the mixture reaches 238°, 3 to 4 minutes. Stir in all of the walnuts and cook until fragrant and toasty and slightly thickened, about 3 minutes longer.
Pour the walnut caramel over the shortbread and let cool completely. Using the parchment paper, lift onto a cutting board. Cut into bars and serve.
The bars can be refrigerated for up to 5 days.