Bolognese Sauce with prosciutto

4 tablespoons unsalted butter 4 tablespoons extra virgin olive oil 1 large onion , minced 2 carrots , in small dice 2 large celery ribs , in small dice 1 1/2[...]

4 tablespoons butter 4 ounces pancetta , finely chopped 2 medium carrots , finely chopped 4 medium celery ribs , peeled and finely chopped 1 medium onion ,[...]

1 teaspoon olive oil 1 medium onion , finely chopped 2 stalks celery , finely chopped 2 small carrots , finely chopped 12 ounces ground veal or 12 ounces[...]