In a frying pan start to heat oil , enough to cover fries. do not over crowd pan.do in batches and place on paper towel to drain some oil.

in a med size sauce pot melt 2 tablespoons butter. Add flour and dry mustard wisking constantly about 2min.add beef broth slowly continue wisking, bring to a boil to thicken and turn down flame slightly.when thickened , remove from heat add sour cream and mix well. set aside.

In a second pan add 2 TBL spoons butter to pan on med heat.add onion cook a min then add beef to pan along with salt and pepper.When beef is cooked throughout add sauce mixture to beef.

add beef and sauce to your plate and top with matchstick potatoes and parsley