Nonstick cooking spray
2 cups granulated sugar
1 cup water
½ cup light corn syrup
½ teaspoon coarse salt
2 tablespoons unsalted butter
½ teaspoon baking soda
3 cups salted dry-roasted peanuts (about 1 pound)
1. Line a rimmed baking sheet with parchment paper and lightly coat with cooking spray; set aside.
2. In a medium saucepan, combine sugar, water, corn syrup and salt. Bring to a rapid simmer over medium-high and cook until deep golden, about 20 to 25 minutes. Remove pan from heat. Stir in butter, baking soda, and peanuts (mixture will foam). Stir until mixture is no longer bubbling and caramel is smooth, 1 minute.
3. Transfer to the prepared baking sheet and spread with a lightly greased spatula. Let cool until firm, 15 minutes. Break into pieces. The brittle can be stored in an airtight container at room temperature for up to 3 weeks.