Ingredients

Vegetable oil cooking spray 

4 sticks unsalted butter 

2 2/3 cups sugar 

1/3 cup water 

1/4 cup light corn syrup 

Salt 

8 ounces bittersweet chocolate, melted 

2/3 cup finely chopped toasted hazelnuts 

Preparation

Coat a 12-by-17-inch rimmed baking sheet withcooking spray, and line with parchment. Melt butterand sugar in a medium saucepan over medium-high heat. Add water and corn syrup. Cook until a candy thermometer reaches 300 degrees. Add 1/2 teaspoon salt. Stir to even out color. Pour mixture onto baking sheet without spreading. Let cool.

Spread chocolate over top, and sprinkle with hazelnuts. Refrigerate until firm, about 45 minutes. Break into pieces.