Shell the cannellini beans and discard the pods. Rinse the beans thoroughly in cold water. Place them in a pot with a sage leaf and plenty of cold water (the water should cover the beans by about 2 inches). Bring to a boil and cook for about 30 minutes after boiling begins.

Prepare a vegetable broth using your choice of vegetables. Meanwhile, clean the shrimp, reserving the heads and shells, and remove the intestinal vein.

Slice the leek into rounds and dice the potato. Finely chop the rosemary.

To make the creamy bean sauce: In a pot, sauté 4/5 of the leek in a little extra-virgin olive oil.

Add the broth, potato, and rosemary. Season with salt. Cook for 30 minutes, then blend until smooth.

While the sauce is cooking, prepare the shrimp bisque: Sauté a little leek and a few black peppercorns in a small amount of extra-virgin olive oil. When the leek softens, add the shrimp heads and shells. Deglaze with 1 cup of white wine and press the heads to release their juices.

Once the alcohol has evaporated, add about 2 cups of ice-cold water and bring to a boil. Cook for 10 minutes, then strain and reduce the liquid.

In a skillet, quickly sauté the shrimp in hot extra-virgin olive oil for a few seconds. Deglaze with wine and remove from the pan. Let cool, then roughly chop the shrimp, reserving a few whole for garnish. Mix the chopped shrimp with the buffalo ricotta to make the cannelloni filling.

Boil the cannelloni noodles in plenty of salted water, then briefly sauté them in the shrimp pan juices. Fill them with the ricotta and shrimp mixture.

In a skillet, fry some leek in sunflower oil until crispy.