You’ll Need:For the Bolognese sauce 6 tablespoons unsalted butter 6 tablespoons extra-virgin olive oil 1 pound ground beef 4 ounces prosciutto (se Note No. 2 below) 4 ounces pancetta 2 celery stalked, trimmed and chopped 2 large carrots, peeled, trimmed and chopped 2 onions, peeled, trimmed and chopped 2 to