Begin by preheating your oven to 180°C (350°F) and either grease a square 20cm x 20cm baking tin or line it with parchment paper.

In a heat-resistant bowl, combine the 200g of chopped white chocolate and unsalted butter. You can melt this mixture in the microwave, heating it in 20-second intervals, or use a double boiler. Stir until it becomes smooth, then allow it to cool slightly.

In a separate mixing bowl, thoroughly whisk together the caster sugar and eggs until they are well blended.

Gradually pour the melted chocolate and butter mixture into the sugar and egg mixture, while continuously whisking. Add the vanilla extract and continue to mix until the mixture is smooth.

Sift the plain flour and a pinch of salt into the wet ingredients. Gently incorporate the dry ingredients into the wet mixture, being cautious not to overmix.

Add the white chocolate chips into the batter, ensuring they are evenly distributed.

Transfer the blondie batter into the prepared baking tin, spreading it out evenly.

Bake in the preheated oven for about 25-30 minutes, or until the top takes on a golden brown hue, and when a toothpick is inserted into the centre, it comes out with a few moist crumbs (not wet batter).

Allow the blondies to cool within the tin for approximately 15-20 minutes before transferring them to a wire rack to cool completely.

Once they have fully cooled, cut the blondies into either squares or rectangles.