Cipolline sott’Aceto alla Bolognese

When serving Bologna’s magnificent pork specialties—prosciutto, salami, mortadella—as antipasto, one usually accompanies them with an assortment of vegetables pickled in vinegar or preserved in olive oil. One of the most pleasing of such accompaniments are these home-pickled onions. There is a lively crunch to their consistency, and they have a judicious measure of tartness, enough to freshen the palate between helpings of meat, yet not so much to sting it. They are so easy to take t