Tofu, Fennel and Prawn Gyoza

• 1 packet (25–30) gyoza wrappers

For the filling, wrap the tofu in paper towels and place on a plate. Place a board on top of the tofu and a bowl of water on top of the board as a weight. Let the tofu drain for 30 minutes. Peel the prawns, then chop with a large knife until they have a paste-like texture. Chop the fennel and toss with the salt, then leave for 10 minutes before squeezing out the excess liquid with your hands. U