Mom’s Beef Stroganoff

### Ingredients
* 1 pound beef chuck roast or steaks
* 4 Tbsp butter
* 1 small onion, minced
* 2 Tbsp all-purpose flour
* 500ml beef broth
* 1 teaspoon dry mustard
* 1 cup sliced mushrooms
* 1/2 cup plain greek yogurt
* salt & ground black pepper to taste
* 1 package egg noodles

### Method
1. Remove any fat and gristle from the roast and cut into strips 1/2 inch thick by 2 inches long.
1. Season beef with salt and toss with dry mustard and flour to coat
1. In a large skillet over medium heat, melt the butter and brown the beef strips quickly, then push the beef strips off to one side.
1. Add the onions and mushrooms and cook slowly for 3 to 5 minutes, then push to the side with the beef strips.
1. Pour in beef broth and bring to a boil, stirring constantly. Lower the heat and stir in mustard. Cover and simmer for 1 hour or until the meat is tender.
1. Add salt & fresh ground pepper to taste
1. Serve with sour cream over noodles