Meanwhile, cut the onion and garlic and fry in a tablespoon of olive oil until translucent. Then add the beans and fry them briefly. Pour in the vegetable stock and let everything simmer on a low flame for about 5 - 10 minutes. Salt and pepper. Then pour everything into a tall vessel and puree with the hand blender.
Sauté the remaining 2 tablespoons of oil with the thyme and some fresh lemon zest in a pan for about 1 - 2 minutes. Pour the puree into a bowl and drizzle the thyme-lemon oil over it.