Mortadella

Name: Stuffed onions Ligurian style
Prep time: 50 min
Cook time: 20 min
Total time: 70 min
Ingredients: 4 white onions (large); 600 g potatoes; 300 g zucchinis; 50 g mortadella; 1 egg; 60 g parmesan cheese; breadcrumbs; salt; pepper; nutmeg; olive oil extra virgin