Clean and peel all the vegetables. Cut the potatoes and carrots into cubes and slice the onions. Put the butter in a high-sided pan and turn on a low flame.

Add all the vegetables and sauté for about 10 minutes. Add the hot vegetable broth and continue cooking for another 30 minutes. Blend everything with an immersion blender and season with salt.

Brown the bacon in a pan without adding any other fat. Drain on absorbent paper and chop roughly. Pour the soup into individual soup bowls, garnish with the chopped bacon and a drizzle of oil.

Complete with flakes of spicy Provolone Valpadana DOP, sprinkle with black pepper and serve.