Onion cipolline with balsamic vinegar modène 1,5kg

This very simple recipe, with onions, balsamic vinegar of Modena PGI, sugar and salt, preserves the fragrance of the "borettane" onions, a variety that is both strong in taste and very sweet in the mouth, The result is crunchy and very aromatic, Very appreciated as a condiment, especially as an accompaniment to Italian cold cuts, they can also be served as a garnish for beef or chicken, or in a salad with sardines or tuna in olive oil,,,