Beefsteak with mushrooms and cooking cream

First, cut the meat into sticks, mushrooms into quarters, and chop the onion. In a pan, add sliced ​​meat to the butter and oil mixture, season with salt and pepper and fry, turning for 3-4 minutes. Take out the finished meat, put it on warm place. Add the onion to the frying fat, season with salt and sugar, and stir and fry until the onion softens. Transfer the fried onion to a sieve, press it into a clean pan so that the sauce is smooth, add the champignons and fry over medium heat for about 3 minutes. Then add the meat, chopped parsley, cooking cream, stir and wait for the ingredients to warm up. The dish is ready, and you can serve it.