Sourdough is bread for the connoisseur, and is Paul Hollywood's passion. Today he shares how to cultivate a sourdough starter, harnessing natural yeasts to leaven your bread. He starts with a classic sourdough and from this basic recipe, he makes the ultimate sweet bread, a white chocolate and raspberry sourdough and a fruit packed summer pudding. But for a real family feast, Paul serves tuna nicoise salad with tapenade and a stunning, leaf shaped sourdough fougasse bursting with olives.