A layer of smooth chocolate and chopped hazelnuts disguises the top of this brittle as a candy bar.
- Vegetable oil cooking spray
- 4 sticks unsalted butter
- 2 2/3 cups sugar
- 1/3 cup water
- 1/4 cup light corn syrup
- 8 ounces bittersweet chocolate, melted
- 2/3 cup finely chopped toasted hazelnuts
Coat a 12-by-17-inch rimmed baking sheet with cooking spray, and line with parchment. Melt butter and 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.