Try to break through the Chocolate as soon as you can and keep crushing until you can feed the Candy Fog. When it's full, move it into the 3x3 quadrant to collect the Liquorice Swirls. You don't have to let Chocolate grow, there are already 45 pieces of it at the begining of the game, and the more it multiplies, the harder it will be for you to make special candies.
And you need them, because when they are set off, more blue candies are cascaded.
Watch the video below, for a better guide: