Russian
Finely chop the onions.
Heat the oil in a large deep frying pan over medium heat and fry the onions for 5-6 minutes until soft and golden.
Add the ground beef, raise the heat and fry for 10-12 minutes, breaking up the lumps with a spatula, until the liquid has evaporated and the meat is browned. Season with 1 tsp salt and the pepper.
Meanwhile, bring the water to a boil with 1 tbsp salt, add the pasta and cook until al dente according to the package, 9-11 minutes.
Drain the pasta and add it to the pan with the meat together with the butter.
Toss over low heat for 2-3 minutes so the pasta absorbs the meat juices and fat.
Serve hot, with pickles or a fresh vegetable salad on the side.