Peanut Butter Stuffed Brownies

Step 1: Grease a 20 cm/8-inch square pan with butter, then line it with baking paper.

Step 2: Set aside 2 tablespoons of the peanut butter for the swirls. Warm the remaining peanut butter in the microwave for about 30 seconds on high to loosen it, then pour it into the prepared pan and spread evenly. Sprinkle with half the salt flakes. Freeze for 2 to 3 hours, until firm enough to lift. Lift it out of the pan using the paper, then return it to the freezer on the paper while you make the batter; it softens quickly.

Step 3: Line the pan again with baking paper, leaving an overhang so you can lift out the brownies.

Step 4: Preheat the oven to 180°C/350°F (160°C fan-forced).

Step 5: Put the butter and chocolate in a heatproof bowl. Microwave in 30-second bursts, stirring between each, until melted and smooth; this takes about 1 minute 30 seconds. Stir to combine.

Step 6: Add the sugar and mix. Add the eggs and vanilla and mix well until smooth. Add the flour, cocoa and salt, then stir until smooth.

Step 7: Pour half the batter into the lined pan. Top with the frozen peanut butter slab, then spread the remaining batter over it.

Step 8: Dollop or drizzle the reserved 2 tablespoons of peanut butter randomly over the surface. Use a butter knife or teaspoon to make swirls; make grooves if needed to reveal some brownie batter.

Step 9: Bake for 32 minutes. The middle will still jiggle, but it will set as it cools; the edges should be fairly firm.

Step 10: Cool the brownies in the pan on the counter for 1 hour, then refrigerate for at least 3 hours so they set before cutting. Cut into 16 squares. Let them come to room temperature for at least 15 minutes before serving. Store in an airtight container in a cool, dry place.