Pre-heat the oven to 180°c and line a 30x30 cake tin with greaseproof paper.
In the bowl of a mixer, beat the melted butter and sugar together. add the eggs and vanilla and mix well.
Sift in the flour, baking powder and salt and mix until the just mixed in.
Fold in the almonds, coconut and white chocolate then transfer the batter to the prepared baking dish and bake for 20-25 minutes until a skewer inserted comes out with moist crumbs attached (blondies can dry out and over-bake easily so rather underbake them slightly).
Allow to cool for 20-30 minutes before cutting and serving.