First, press the tofu using a tofu press or place it between two clean tea towels, lay it on a plate and put a weight on top
Leave for at least half an hour to drain any liquid and firm up before you start cooking
Carefully slice the pressed tofu into 1cm-wide sticks and spread them out on a board
Sift cornflour over the top, coating the pieces generously
Use tongs or two forks to turn the pieces and sift over more cornflour until the tofu is covered on all sides. The thicker the better with the cornflour as this coating gives the cooked tofu its crunchy texture
Pour enough oil into the pan to fully coat the bottom and heat until it makes the tip of a wooden spoon sizzle
Carefully place the tofu pieces in the pan, with a bit of space around each one (you may need to cook them in batches)
Cook for 5 minutes, turning the pieces every minute or so until they are starting to turn golden brown
Transfer to the plate lined with kitchen paper
Tip away the excess oil in the pan and reduce the heat to medium-high
Cut the lemons in half and squeeze the juice into the pan, catching any pips in your other hand (be careful as the pan may spit)
Add the orange juice, sweet chilli sauce, sriracha and soy sauce and bring to the boil
Simmer for 5-7 minutes until the liquid has reduced to a syrupy consistency
Add the tofu strips back to the pan and stir until fully coated
Continue to cook, stirring regularly, for 5 minutes and then remove from the heat
Finely slice the spring onion and sprinkle over the tofu along with the sesame seeds before serving
