Ingredients:

  • 2 cups (400g) light brown sugar, packed
  • 1/2 cup (115g) unsalted butter
  • 1/2 cup (120ml) whole milk
  • 1/4 tsp salt
  • 1 cup (250g) creamy peanut butter
  • 1 tsp pure vanilla extract
  • 1 1/2 cups (180g) confectioners' sugar, sifted

Instructions:

  1. Line an 8x8-inch baking pan with parchment paper, leaving an overhang on two sides. Measure all ingredients before starting.
  2. In a heavy-bottomed saucepan over medium-high heat, combine brown sugar, butter, milk, and salt. Stir constantly until the butter melts and sugar dissolves.
  3. Once the mixture reaches a rolling boil, stop stirring. Insert a candy thermometer and continue boiling until it reaches 234°F (112°C), the soft-ball stage.
  4. Immediately remove the pan from heat. Stir in the peanut butter and vanilla extract until the mixture is glossy and thick.
  5. Fold in the confectioners' sugar until no white streaks remain and the mixture is smooth.
  6. Pour the mixture into the prepared pan and smooth the top. Let it set at room temperature for at least 2 hours before lifting out and slicing into 1-inch squares.