I have used a minimal amount of white chocolate in this recipe, which does allow the salted caramel to shine but unfortunately makes the ganache more difficult to handle. If it is kept cold at all stages of truffle creation, it will work. I promise. If you find the mixture too difficult to handle, add another 100g white chocolate to the ganache. This will dull the flavour of the salted caramel slightly, but the truffles will still be very delicious.