Tempering is the process of heating then cooling chocolate to form a specific type of crystals in the cocoa butter. If we simply melt and cool shop- bought chocolate, it will quickly ‘bloom’, with dots and streaks of cocoa butter. It melts quickly when touched too. Tempered chocolate will quickly set hard and shiny, won’t bloom, and shrinks as it cools, making it easy to remove from a mould. Here’s a simple method: Break up 3/4 of the chocolate into a heatproof bowl. Melt until it is flowing and smooth. White chocolate should reach 43C, milk and dark 45C. Add the remaining chocolate, chopped into small pieces. Stir with a spatula until the pieces have melted and the thermometer shows 28C for milk and white, 30C for dark. This can take a while, so have patience and keep stirring. Use as soon as possible. If the chocolate starts to get too cold and thick as you use it, heat for just a few seconds and stir well.