Start by draining the soaked cannellini beans and placing them in a large pot filled with water. Bring the water to a rolling boil over high heat and let the beans cook for 3-4 minutes, then strain them.

In the same pot, heat 2 tablespoons of olive oil over medium heat. Add the minced onion and finely chopped garlic, then sauté them for 5-7 minutes until the onion becomes translucent and fragrant.

Once the onions and garlic are beautifully sautéed, add the prepared beans back into the pot along with 1.5 liters of water or vegetable stock. Stir well to combine everything, then bring the mixture to a rapid boil.

Reduce the heat to low and cover the pot, allowing the soup to simmer gently for about 2 hours. Halfway through cooking, toss in the finely chopped celery and thinly sliced carrot.

After the beans are tender, season your soup with kosher salt and freshly ground pepper to taste. Stir in the juice and zest of one fresh lemon just before serving.