Grease & line a 20cm/8" square cake tin with parchment paper
In a large, heavy-bottomed skillet pan add the dessicated coconut and shake to level out. Put the pan in the oven for about 3 minutes. Take the pan out of the oven and give the contents a stir and shake to level out again. Keep doing this until the coconut is uniformly golden brown. Set aside to cool. You could do this step on a stove-top using a wok or other steep-sided pan
In a large mixing bowl and using a wire balloon whisk, cream the butter & caster sugar until light and fluffy
Add the egg and whisk until fully incorporated
Mix in the vanilla extract
Sift over the plain flour and baking powder. Fold in using the spatula
Stir in the white chocolate and cooled, toasted dessicated coconut until well mixed in
Spoon the mixture into the prepared cake tin and level out using the spatula or the back of a spoon. Make sure to push the blondie dough into the corners
Bake for 20 minutes, until the top turns a lovely golden brown
Remove from the oven and leave the blondie in the tin for 5 minutes. Lift the blondie (still in the parchment paper) and allow to cool completely on a wire rack