Beef Stroganoff

One of my (very many) favorite meals for Winter.  My only complaint:  I ALWAYS overcook the beef.  It really only needs to cook for 5 minutes, and I never get the timing quite right.  Still, a problem with my timing, not the recipe.

It only takes a half hour to make, including time to slice the onions, mushrooms, and steak. 

Makes 4 servings; from How to Cook Everything.

Ingredients:
3 T butter
2 large onions, sliced
8 oz. mushrooms, sliced
1-1/2 lbs. beef tenderloin or sirloin, cut into 1-in. chunks
1 T Dijon mustard
1 c. beef stock (I used canned)
1/2 c. or a little more sour cream
Salt and pepper to taste 

Directions:
1.  Melt butter in a large, deep skillet with a lid; add onions and mushrooms with some salt and pepper.  Cook over med-low heat until the onions are soft but not brown.  Add the beef and cook for 1 minute (I overdid this-- possibly stopping to take pictures isn't a good idea.)

2.  Stir in the mustard and the stock; turn up the heat until mixture is bubbling.  Cook until meat is tender (about 5 minutes)-- I think that I overcooked this step, too.  Stir in the sour cream, taste, and add more salt, pepper, or mustard if desired. 

3.  Serve over rice or egg noodles.  Stoically ignore any optimistic critters who would prefer stroganoff to dog food for dinner.  Then put a little sauce on top of their kibble, because you're not made of stone.