Preheat oven to 180-190c, line baking tray with the celeriac and herbs and bake for around 30 minutes.
In a large pot heat some olive oil, add leak, apple and onion to cook until soft and translucent.
Add the roasted celeriac and bay leaves then cover with vegetable stock. Bring to boil and then reduce the heat and let the soup simmer for 30 minutes.
Take the pot off the head and remove the bay leaves, making sure that all the ingredients are soft and ready to blend with a stick blender.
Season with salt & pepper to takes. (if the soup is too thick you can add a little almond or oat milk)
To serve top with toasted walnuts, apple slices and a dash of yoghurt or cream.