Prepare the Parmesan cheese rind by cleaning and soaking it in warm water.

Slice the green cabbage into thin strips or use a food processor to shred the leaves.

In a large pan, heat the olive oil over medium heat.

Add the chopped onions and diced pancetta.

Sauté until the onions are translucent and the pancetta is lightly browned.

Add the shredded cabbage and the soaked Parmesan cheese rind to the pan.

Cover and let it simmer for about 10 minutes.

Once the cabbage is almost tender, add the Arborio rice to the pan.

Stir well to coat the rice with the oil and mix it with the cabbage mixture.

Gradually add the hot broth to the rice mixture, one ladleful at a time, stirring constantly.

Allow each addition of broth to be absorbed before adding more.

This process should take about 20 minutes.

After about 20 minutes, the rice should be creamy and tender.

Stir in the grated Parmesan cheese and butter (if using) until well combined.

Season with salt and pepper to taste.

Let the risotto rest for about 15 minutes before serving to allow the flavors to meld.

Serve the risotto with extra Parmesan cheese on top.