Chop the leeks and add them to a large bowl of cold water. Allow all the sand and grit to sink to the bottom of the bowl. Using your hands or a slotted spoon scoop out the leeks, transfer to a colander and allow them to drain well.
1.5 lb leeks
Preheat a heavy bottom soup put over medium heat. Add a light drizzle of olive oil and saute the leeks with a pinch of salt until wilted and all the moisture has evaporate. Add another light drizzle of olive oil and continue cooking until the leeks start to show a little caramelization around the edges. Stir in the chili pepper / chili flakes if using.
1.5 lb leeks, 1/2 red chili pepper
Add the celery (+ carrot if using) and saute a few minutes until it starts to soften.
2 celery stalks, 1 carrot peeled & chopped
Meanwhile open the San Marzano tomatoes, transfer to a bowl and using your hand crush them just until a rustic texture is achieved. Add to the pot with the leeks together with the rosemary, thyme and bay.
28 oz canned San Marzano tomatoes, 2 sprigs rosemary, 2 bay leaves, 8 sprigs thyme
Open the can of beans, drain and rinse and lightly crush about half of them before adding to the soup pot together with the nutritional yeast and a good pinch of sea salt.
15 oz canned cannellini beans, 2 Tbsp nutritional yeast
Pour in the water and bring to a gentle boil. Partially cover with a lid and cook for a good 35 to 45 minutes.
6-7 cups water
Stir in the chopped kale and cook a few more minutes just until wilted. Remove from heat and adjust seasonings to taste with more sea and chili flakes. Discard the sprigs from rosemary and thyme at this point.
1 bunch Tuscan Lacinato kale, sea salt to taste