Preheat oven to 160°C fan-forced. Grease and line a 20 × 20 cm baking pan with baking paper, leaving a slight overhang for easy lifting.

In a large bowl, whisk together the melted butter, brown sugar and white sugar until smooth and glossy.

Beat in the eggs one at a time until fully incorporated, then stir in the vanilla extract.

In a separate bowl, sift together the flour, baking powder, cornflour and salt. Whisk to combine evenly.

Gently fold the dry ingredients into the wet mixture until just combined. Avoid overmixing to keep the blondies soft and tender.

Place the raspberries on paper towel and pat dry thoroughly. Toss lightly with 1 teaspoon of flour to absorb excess moisture and prevent sinking.

Carefully fold through the white chocolate chunks and raspberries.

Spread the batter evenly into the prepared pan and smooth the top.

Bake for 38 to 42 minutes, or until the edges are lightly golden and the centre feels set but soft when gently pressed. A toothpick inserted near the centre should come out with a few moist crumbs, not wet batter.

Allow blondies to cool completely in the pan on a wire rack before slicing into 9 squares.