A simple, hearty, nourishing soup that is a classic in Portugal. The type of potatoes chosen will affect the final texture of the soup - floury potatoes will collapse and thicken the soup; waxier ones will hold their shape. Both ways are delicious.
A vegetarian soup if you go for a water or vegetable stock. For a meatier option with even greater depth of flavour, you could add slices of cooked chorizo to serve too.
Serves: 4
2 tbsp olive oil
1 onion, finely chopped
2 garlic cloves, finely chopped
2 bay leaves
2 thyme sprigs
rind from a piece of parmesan
4 large potatoes
11/4 litre water, vegetable stock or meat stock
1 head of cavolo nero, approx 200g (or curly kale)
2 tbsp extra virgin olive oil
1 tbsp balsamic vinegar
Heat the olive oil in a medium saucepan, Add the onion and cook for approx 10-15 mins until soft but not coloured, then add the garlic, herbs and parmesan rind and cook for a further couple of minutes. As the veg is cooking, peel the potatoes and cut into cubes. Add them to the pan and stir round for a minute or two so they can take on flavour, then pour in a litre of the stock. Simmer for 20 mins until the potatoes are tender and maybe just starting to collapse.
Lift the herbs and parmesan rind out. Make a decision about the texture of the soup and if you want to add all or some of the remaining 250ml of liquid or not. Tear the cavolo nero leaves away from the ribs of the head, finely slice the leaves and stir into the soup. Let it gently wilt and cook in there for a minute or two over a low heat. Season and divide between bowls to serve, with the extra virgin olive oil and balsamic drizzled over each to finish.
(This recipe originally featured for Borough Market.)