Preheat the oven to 200°C/390°F.

Finely chop the carrot, celery, onion and 1 garlic clove and gently fry in a pan with 2 tablespoons of olive oil for 5 minutes.

Grate the potatoes in the pan, mix well and add the hot broth. Cook until the sauce gets creamy (about 15 minutes).

Cook the pasta and drain it 3 minutes before the suggested cooking time.

Add the saffron to the hot sauce, mix it well with the pasta and put it in a gratin pan.

Grate the provola and sprinkle on top.

Cook in the oven for about 10 minutes, until the cheese is melted and golden.

Remove from the oven and add some freshly ground black pepper.