Preheat oven to 170C conventional/150C fan forced. Grease and line a 20cm square cake tin. 

In a small saucepan, or in the microwave, melt butter over medium heat. When fully melted, take off heat and add Koko Black White Chocolate Dotties, swirl pan to fully immerse the chocolate. Leave to sit for a couple of minutes to allow the chocolate to melt and then whisk until combined. Pour into a mixing bowl and set aside to cool a little. 

To the butter and chocolate mix, add caster sugar and whisk to combine. Whisk in eggs one at a time, then add vanilla extract and whisk well. Sift in flour, add salt and fold in until just combined. Add chopped white chocolate and fold through to distribute evenly. 

Add raspberries and gently fold through until evenly distributed, don’t over mix or the raspberries will break up too much. 

Pour the mixture into prepared pan and bake for approximately 30 to 40 minutes, until a toothpick inserted into the centre comes out with just a few moist crumbs sticking to it. Remove from oven and allow to cool in tin. 

Cut in to squares and serve.