This is a simple, hassel-free, flavourful soup. Serve as is, or with herb croutons.
- 4 Tbsp butter
- 1 medium onion, chopped
- 1 celery stick, chopped
- Salt and pepper, to taste
- 2 cups chicken stock
- 1½ cups potatoes, roughly diced
- 1 large pack watercress
- ½ cup cold milk
- Nutmeg, grated
Place butter, onion, celery, salt, pepper and 4 Tbsp water in a casserole on medium heat. Steam for 5-6 minutes to sweat vegetables, without browing.
Add stock and potatoes. Bring to a boil.
Wash watercress and cut off tough stems to add to soup. Set aside tender sections.
Reduce heat and cook until potatoes become tender, about 35 minutes. Remove casserole from heat and pour in cold milk.
Set aside 2-3 nice cress branches for later use. Chop remaining watercress and add to soup. Reduce to a purée using an immersion blender.
Reheat soup, without boiling and serve immediately.
Serve garnished with watercress leaves, a knob of butter and a sprinkling of nutmeg.