1.Preheat oven to 180°C (160°C fan-forced). Spray 3 x 12-hole (1-tablespoon/20ml) mini muffin pans with cooking oil. Press one wrapper into each pan hole; spray with cooking oil. Bake 7 minutes or until browned lightly and crisp. Cool on a wire rack.
2.Meanwhile, combine tuna, rind, cornichons, herbs, oil, shallots, anchovies and capers in a medium bowl. Season to taste.
3.Just before serving, stir juice into tuna mixture. Spoon mixture into wonton cups; top with cress and extra lemon rind, to serve.
Wonton cups can be prepared a day ahead and stored in an airtight container. You need 3 x 12-hole (1-tablespoon/20ml) mini muffin pans. If you only have one pan, that is fine, just cook the wonton cases in batches. You could also serve the tuna tartare in a bowl with a pile of home-cooked prawn crackers for guests to assemble themselves.