This dish is delicious! I did use 1/4 cup of flour and not just what was needed to coat the meat. Also, I'm not hunting around for hanger steak. Top Sirloin New York Strip worked great for me. I'll try beef stock instead of chicken stock next time, but I doubt it'll make that much of a difference.
I don't recommend this recipe, it's missing a key step in the instructions. After making my sauce would just not thicken. After exploring other recipes online this is because at no point do they have you add the flour to the broth. The only time the flour is mentioned is to coat the beef. This didn't do much for the beef and it absolutely did nothing to help thicken the sauce up. Also the chicken stock gave it a not quite "stroganoff" taste, it should be beef or vegetable broth.
This recipe is so easy and delicious! I used beef tenderloin as I had some left over from a whole roast we did on Christmas. I didn't have fresh thyme but added 3/4 t. dried thyme. I think the 1 T. of Worcestershire sauce made a huge flavor addition! I used wide Amish noodles rather than fettuccini. Will definitely make this again.