Bolognese Sauce (Ragu)

From Mark Bittman's How to Make Everything
Makes about 1 quart

• 2 tablespoons olive oil
• 1 small onion, minced
• 1 carrot, peeled and minced
• 1 celery rib, minced
• 1/4 cup minced bacon or pancetta (or some smoked paprika)
• 1/2 pound lean ground pork (or use all beef)
• 1/2 pound lean ground beef
• 3/4 cup dry white wine (or juice from the tomatoes)
• 1 (28- or 35-ounce) can whole plum tomatoes, drained (reserve juice, if needed instead of wine)
• 1 cup beef or chicken stock, preferably homemade
• Salt and freshly ground black pepper to taste
• 1 cup cream, half-and-half, or milk
• Freshly grated Parmesan cheese (optional)

1. Put the olive oil in a large, deep skillet or saucepan. Turn the heat to medium-low and, a minute later, add the onion, carrot, celery, and bacon or pancetta. Cook, stirring occasionally, until the vegetables are tender, about 10 minutes.
2. Add the ground meat and cook, stirring and breaking up any clumps, until all traces of red are gone, about 5 minutes. Add the wine or tomato juice, raise the heat a bit, and cook, stirring occasionally, until most of the liquid is evaporated, about 5 minutes.
3. Crush the tomatoes wit a fork or your hands and add them to the pot; stir, then add the stock. Turn the heat to low and cook at a slow simmer, stirring occasionally and breaking up the tomatoes and any clumps of meat that remain. After an hour or so, add salt and pepper. Cook for at least another hour, until much of the liquid has evaporated and the sauce is very thick. (This sauce may be covered and refrigerated for a day or two, or put in a closed container and frozen for several weeks. Reheat before completing.)
4. Add the cream, half-and-half or milk and cook for another 15 to 30 minutes, stirring occasionally; taste and add more salt and/or pepper as needed.