Instructions

1. Cut the tofu into 2cm cubes. Cut the pack choi in half (vertically), then halve it again. Thinly slice the leek.
2. Put the stock in a saucepan and add the leek. Cook for 3 minutes then add the pak choi and cook for another 3 minutes or so.
3. Take a spoonful of stock into a small bowl and mix it with the miso and soy sauce until you get a smooth paste. Pour this into the soup and add the tofu pieces.
4. Bring to a simmer (don’t let it boil), then serve with a squeeze of lime juice and the sesame seeds.