Prepare the meat. Fry the chicken fillet in a frying pan with olive oil over medium heat for 5-7 minutes. Place the meat on a plate. Fry the onion in the same frying pan until golden brown, add the chicken, add flour, salt and pepper. Stir, pour in the cream. Boil the sauce until thick. Add half the amount of grated cheese and garlic. Boil the sauce for 2-3 minutes until the cheese melts.
Prepare the fettuccine. Place the pasta in the pan with the meat and sauce. Adjust the thickness of the sauce using the water left over from cooking the pasta. Keep the fettuccine in the pan for 2 minutes.