Instructions

• Line a large rimmed baking sheet with a silicone baking mat or a piece of parchment paper; set aside.
• In a large, heavy-bottomed stock pot or saucepan combine 2 cups granulated sugar, ½ cup water, ½ cup light corn syrup, and 6 tablespoons unsalted butter. Clip a candy thermometer to the pot with the thermometer tip immersed in the sugar mixture but not touching the bottom.
• Heat the mixture over medium-high heat and bring to a boil. Do not stir or otherwise disturb the cooking sugars while they are coming to temperature. Continue cooking until the mixture begins to turn lightly golden and the thermometer reaches 300°F (hard‑crack stage). This typically takes about 12–16 minutes.
• As soon as the thermometer reads 300°F, immediately turn off the heat and, if you are using an electric stove, remove the pot from the burner so the mixture stops cooking.
• Working quickly and carefully (the mixture will bubble), stir in 1 teaspoon baking soda, 2 teaspoons vanilla extract, and 2 cups roasted & salted cashews. Stir just long enough to distribute the ingredients—the baking soda will cause the mixture to foam.
• Immediately pour the hot brittle onto the prepared baking sheet and, using a heatproof spatula or by tilting the sheet, spread the mixture into an even layer (about a 9 × 12‑inch rectangle). Work quickly—the brittle begins to harden almost immediately.
• Let the cashew brittle cool completely at room temperature until hard, then break into pieces.