Break the chocolate into small pieces. Put in a bowl suspended over a pan of simmering water and leave to melt. Remove from the heat and leave to cool for 5 mins. Meanwhile, blow up your balloons – you want each bowl to be about 10cm wide, so try to pick small balloons and don’t blow them up too much. Tie with a knot.
Line a baking tray with parchment. Holding the knotted end of the balloon, dip it into the melted chocolate to create your bowl shape. Stand it on the tray and hold the balloon for a few secs until the chocolate pools around the base allowing you to let go of the balloon. Continue with the remaining balloons. Chill for at least 30 mins or until set.
When the chocolate has set, pop the balloons and carefully peel them away from the bowls. Fill with your chosen dessert – ice cream is good because it keeps the bowls cold.