Make old-fashioned peanut brittle at home with this easy recipe. A crunchy, buttery Christmas candy that’s perfect for gifting and keeps beautifully through the holidays.
Line a large baking sheet with a silicone baking mat or parchment paper. Set aside.
In a heavy 2-quart saucepan, combine the sugar, water, butter, and corn syrup over medium-high. Cook, stirring occasionally, until the caramel is light brown and registers 300°F on a candy thermometer, 10 to 15 minutes.
Remove from the heat and immediately stir in the nuts, baking soda, and vanilla until just combined. The mixture will bubble.
Quickly scrape the brittle onto a large rimmed, nonstick baking sheet. Using the back of a large rubber spatula (oil it lightly if it sticks), spread the brittle into a thin, even layer. Sprinkle evenly with salt.
Let cool completely, about 30 minutes. Break the brittle into large shards.