Bolognese Sauce - cooking recipe

Ingredients

2 tsp olive oil
3 oz pancetta, finely chopped
1 large onion, finely chopped
1 medium carrot, finely chopped
2 None celery stalks, finely chopped
1 1/3 lbs ground beef
5 oz chicken livers, trimmed and finely chopped
1 cup milk
3 tbsp butter
1 1/2 cups beef stock
1 cup red wine
1 can (14 oz) tomato puree
2 tbsp tomato paste
1 1/2 lbs spaghetti
1/4 cup chopped fresh flat-leaf parsley
None None Shaved Parmesan cheese, to serve

Preparation

Heat oil in large saucepan on medium-high heat. Cook pancetta, stirring, until crisp. Add onion, carrot and celery; cook, stirring, until vegetables have softened.
Add ground beef and liver to pan; cook, stirring, until ground beef is browned all over. Stir in milk, butter, stock, wine, tomato puree and paste. Transfer mixture in a 4.5-quart slow cooker. Cook, covered, on low, for 8 hours.
Cook pasta in large saucepan of boiling salted water according to package directions. Drain.
Add parsley to sauce; stir. Serve sauce on pasta and sprinkle with Parmesan cheese