Beef Stroganoff

1.5-2lbs top round
salt & pepper
5 Tbsp butter, divided
4 Tbsp flour
1 carton beef broth
1 Tbsp dijon mustard
1 cup sour cream (light is okay)
1 Tbsp olive oil
1/2 Spanish onion, diced
1 lb extra wide egg noodles

Heat skillet over med-low heat with 1 Tbsp butter and 1 Tbsp olive oil.  Add onion and let it sweat.  
Slice meat into 1/4 inch x 2 inch strips.  Salt & pepper the meat and add to the onion.  Brown.
In another skillet, melt remaining butter with flour to create a roux.  Pour in most of the container of the broth.  (I used about 3/4.)  Whisk well.  Let thicken for a minute or two.  Once thickened, whisk in mustard & sour cream.  Thicken another 3-5 minutes.  If it isn't thick enough, make a slurry with about 1 Tbsp cornstarch and 2 Tbsp of the liquid.  Salt & pepper.  Add meat & onions to the sauce.  Heat through and serve over egg noodles.

It was a bit to mustardy for me so next time I'll cut back on that.
(I found this while blog hopping the other day.  I feel bad that I can't remember where it's from to give the creator some credit.)