Rigatoni Con Le Cipolle (Pasta With Onion)

• 3 tablespoons olive oil
• 3 large Spanish onions, thinly sliced
• 1 tablespoon tomato puree
• 4 fluid ounces chicken stock (homemade or made with water and 1/2 stock cube)
• 12 12 ounces macaroni noodles or 12 ounces penne pasta
• 1 slice butter
• 2 ounces parmesan cheese or 2 ounces Mature cheddar cheese, grated
• salt & freshly ground black pepper

1. Heat the oil in a heavy frying pan and cook the onions over a very low heat, stirring occasionally, until they are very tender and golden in colour, approx 30 minutes.
2. Dissolve the tomato puree in the stock; add to the onions and season to taste.
3. Cook the pasta al dente; drain and pour into a serving dish with the knob of butter.
4. Stir in the hot onion sauce, toss with the cheese and serve.

olive oil, spanish onions, tomato puree, fluid ounces chicken stock, macaroni noodles, butter, parmesan cheese, salt

Taken from www.food.com/recipe/rigatoni-con-le-cipolle-pasta-with-onion-341726 (may not work)