From Melissa Hemsley’s Eat Happy Cookbook: “Watercress is one of my favorite greens―delicious raw in salads or lightly cooked in soups and stews. Its pepperiness balances the sweetness of the peas in this really quick green soup. If you can’t get watercress, substitute with spinach, which you could keep in the freezer with the peas, to make this a great store cupboard and freezer standby. The cooked white beans (or any beans of your choice) add extra creaminess and make this soup really satisfying. If you like, you could add a swirl of Tahini Lemon Drizzle (recipe below) or Garlic Yoghurt. I love this soup with toasted Quick Quinoa Bread and butter.” —Food52
Melt the butter in a wide saucepan, add the onion and fry over a medium heat for 6 minutes to soften. Add the garlic to cook for the last 30 seconds.
Add the beans and stock. Bring to a simmer over a medium-high heat and cook for 2 minutes. Add the frozen peas to cook for another minute.
Drop in the watercress and mint leaves, stir and remove from the heat―the green leaves will wilt in the hot liquid.
Add the lemon juice and some salt and pepper, then transfer to a blender, or use a hand-held blender, and whizz into a smooth, creamy soup. Taste for seasoning and serve with a drizzle of olive oil and some extra mint and watercress leaves.
For the lemon tahini drizzle: Whisk all of the ingredients together. Drizzle over each soup portion to your liking.