Prepare and cook (if needed) protein of choice (to add to soup once cooked).
Heat oil over a medium to high heat in a large saucepan. Add leek and ginger and cook for five minutes, or until leek has softened.
Add carrot, zucchini, and mushrooms to the saucepan and stir.
Add 1.25L of stock, cover and bring to the boil.
Once boiling add the dry soba noodles and ensure they are covered with stock before adding the cabbage on top. (Note: the cabbage may not be submerged in water, this is ok, it will reduce while cooking, DO NOT STIR after adding the noodles and cabbage) Cover, bring back to the boil and simmer for five minutes or until noodles are cooked. Stir cabbage through the soup and remove from the heat.
Combine the remaining 250mL of stock with miso paste and soy sauce, making a slurry. Once the soup has been removed from the heat, mix the miso, soy slurry into the soup and add your protein of choice.
Serve topped with 1 tsp sesame seeds, chilli and thinly sliced spring onion.
Enjoy!