Vegan Udon Noodle Soup

Name: Vegan Udon Noodle Soup
Ingredients: 400g firm tofu; 1 tablespoon plain white flour; 1.5 tablespoons water; 4 tablespoons panko breadcrumbs; Oil to fry (fill a pan to about 4cm deep with a neutral oil, like sunflower); 1 litre mushroom stock (or vegetable stock); 2-3 tablespoons white miso paste; 2 tablespoons dark soy sauce; 2 teaspoons toasted sesame oil; 2 teaspoons fresh ginger (peeled and grated); 3-4 cloves garlic (peeled and minced); 1 tablespoon groundnut oil; 300g chestnut mushrooms; 300g udon noodles; 2 pak choi; 1 spring onion (thinly sliced)