1.Bake tartlet cases according to directions on the packet.
2.Meanwhile, stir sugar, butter and cream in small saucepan until sugar dissolves. Reduce heat, simmer, uncovered, without stirring, 2 minutes. Cool 5 minutes. Stir in chocolate and extra cream, refrigerate 10 minutes.
3.Spoon mixture into tartlet cases, sprinkle with nuts and sifted cocoa.