1 Tbsp. unsalted butter at room temperature
3 cups raw peanuts
4 cups sugar
Grease a rimmed baking sheet with 1 Tbsp. butter and set aside. Heat oven to 375 degrees F. Place peanuts on the rimmed baking sheet and roast until they're fragrant and lightly toasted, about 5 minutes. Transfer to a bowl and set aside to cool. Place sugar in a large, heavy-bottomed pot over medium heat. Stir sugar every few minutes to break up any sugar lumps until the sugar is dissolved. Cover the pot (the condensation prevents the sugar from crystallizing) and cook, stirring every 2 minutes, for 10 to 12 minutes or until the sugar is between brown and amber. Remove cover, increase the heat to medium-high, and add the peanuts. Stir to completely incorporate and then carefully transfer the hot Peanut Brittle to the greased baking sheet. Using a rubber spatula, spread the brittle into a 1/2-inch-thick layer. Set aside to cool completely and then chop into chunks. Peanut brittle lasts for weeks. Store in a sealed container.