Freeze the Biscoff slab

• Spread half of the Biscoff spread into a flat slab on baking paper.
• Freeze until firm.

Make the blondie batter

• Melt the butter and whisk it with the brown sugar until smooth.
• Whisk in the eggs and vanilla extract.
• Fold in the flour, baking powder and salt until just combined, then stir in most of the white chocolate chunks.

Layer the blondies

• Spread half of the batter into a lined baking dish.
• Place the frozen Biscoff slab on top and cover with the remaining batter.
• Scatter the rest of the white chocolate chunks over the top.

Bake

• Bake at 180 °C until the edges are set and the centre is still slightly gooey.
• Let cool completely in the dish.

Drizzle and slice

• Warm the remaining Biscoff spread and drizzle it over the cooled blondies.
• Cut into squares and serve.