Wash all the vegetables (celery, carrot, purple turnips, potato, savoy cabbage) thoroughly in cold water and peel them as needed. Dice the celery, carrot, purple turnips, and half the potato into 1/2-inch (about 1 cm) cubes. Slice the savoy cabbage into thin strips and grate the other half of the potato using a coarse grater. If you’re using dried borlotti beans, cook them ahead of time (starting from dried beans, cold water, and bay leaf), and set aside the amount needed for this recipe.

Peel the garlic clove, mince it finely, and sauté it over low heat in a pot with 1 tablespoon of extra virgin olive oil. As soon as it starts to turn golden, add the prepared vegetables (except the savoy cabbage), stir well, and let them cook for a few minutes until lightly browned.

Add hot vegetable broth and the fresh herbs (sage and rosemary). Bring back to a boil and cook for about 30–40 minutes. Season with salt to taste.

About 10 minutes before the end of cooking, add the savoy cabbage, peas, and borlotti beans to the pot, letting the flavors blend together.

While the minestrone is cooking, wash the fennel fronds well, dry them, and chop them finely. Mix them in a small bowl with the remaining olive oil and a pinch of salt.