Lay the silicone molds out on trays that you will easily be able to transfer to the fridge later. Cut the vanilla pod in half and scrape out the seeds with the back of a knife, and set the seeds aside for later. Discard the pod or use it to flavor other recipes.
Add the cacao butter, coconut butter/creamed coconut, and cashew butter to a large heat-resistant bowl and place on top of a saucepan with simmering water (known as a bain-marie or water bath). Make sure the water does not touch the bowl but allow the steam to rise up and gently melt the ingredients. Be careful that absolutely no water splashes into the bowl as water will cause the chocolate to seize. Whisk until melted and smooth.
Remove the bowl from the water bath and add the icing sugar. Whisk well until the sugar has been incorporated into the chocolate mixture. Then add the vanilla and salt and whisk again until the ingredients are evenly mixed.
Divide the chocolate into the silicone molds and place them in the fridge to chill for at least 20 minutes. If adding nuts or fruit add these on top of the chocolate once it's in the molds. Once set, remove the bars from the molds and wrap them in baking paper, and place it in an airtight container. Store in the fridge for up to 2 weeks.
Add freeze-dried raspberries or strawberries or dried fruit such as cranberries to these bars.
Add nuts such as pistachios, roasted hazelnuts, flaked almonds or macadamia nuts.
Lucuma powder adds a wonderful slight caramel flavour to the white chocolate. Add 1-2 tablespoons when adding the icing sugar and mix well.
You can add any powders such as matcha (for green white chocolate), maca powder or beetroot powder (for pink white chocolate). Use these powders sparingly and make sure you sift them to remove any lumps before mixing them into the melted chocolate.
Add some toasted coconut or shredded coconut to these bars for a delicious coconut white chocolate bar.
To keep this vegan white chocolate nut free, you could try swapping out the cashew butter for sunflower seed butter.
You could also use a natural sweetener such as Erythritol or Steviol Glycosides. Bear in mind that unless the sweetener you use is powdered, you will have little 'sweetener' crystals in the finished product