Classic Bolognese Sauce

This is the ultimate meat sauce recipe. I have never had better and I will definitely make this over and over.
Pasta with marinara sauce is my favorite meal but it is nothing compared to this. The three meats all add there own distinct flavors to this sauce. I like to use 2 parts beef to one part veal so the veal does not over power the beef.
The time spent is well worth the effort. The prize... A delicious meal. The celery leaves add a nice flavor and crunch on top of the sauce.

Ingredients

• 2 cups whole milk
• 1/4 cup extra-virgin olive oil
• 1/4 pound pancetta, finely diced
• 4 ounces trimmed chicken livers, finely diced, optional, but recommended
• 2 small onions, finely chopped
• 2 small ribs celery, finely chopped, with leafy tops, chopped
• 1 large carrot, peeled and finely chopped
• 6 cloves garlic, chopped
• 2 small sprigs fresh rosemary, leaves picked and finely chopped
• 2 fresh bay leaves
• 2 1/2 pounds ground beef (chuck or sirloin) and veal mix
• Kosher salt and freshly ground black pepper
• Freshly grated nutmeg
• 2 pinches ground cloves
• 1 1/2 cups dry white wine (about 1/3 bottle)
• 2 cups beef stock
• 2 cups chicken or vegetable stock
• 2 (28-ounce) cans Italian pureed tomatoes
• 1 pound pasta
• 3 tablespoons butter
• Grated Parmigiano-Reggiano cheese

Directions

You know you love it and you know you make it your own special way if you've ever made it before. Here is my take on the classic, if only to be used as a helpful reminder to make-ahead a batch especially in the winter months.

Warm 2 cups milk in small pot over lowest heat.

Heat 1/4 cup olive oil in a large Dutch oven over medium to medium-high heat. Add the pancetta and cook until lightly brown. Then add the chicken livers, and cook almost through. Add the onions, celery, carrots, garlic, rosemary, and bay leaves, and cook until tender, 10 minutes.

Add the ground meat and cook through breaking into pieces, but do not brown. Season with salt, pepper, nutmeg, clove, and stir in the wine and allow it to cook into the meat, 2 to 3 minutes. Add the warm milk to the meat and allow it to absorb into the meat for 1 minute. Stir in the beef stock, vegetable stock, and tomatoes. Bring to a simmer, then reduce the heat and simmer over low heat for 2 hours, stirring occasionally.

Divide the sauce in 1/2, cool, and freeze one batch. Cool and store the remainder for a make-ahead meal within the week. Alternately, cook pasta to al dente, thin the sauce a bit with a bit of starchy pasta water and toss with pasta dressed with butter to combine. Top with grated cheese and chopped celery leaves. Serve with green salad.