For the four of us (remember I have two young men–hardy eaters in their 20s), I used:

2 1/2 pounds of beef top sirloin, about 3/4 ” thick  (the quality of the beef makes all the difference)

6 TBLS of butter (3 TBL for each 1 and 1/4 lbs of meat that you brown)
1 Cup of chopped onion
1 large clove of garlic chopped or pressed
1/2 pound mushrooms, sliced, or 2 cans of sliced mushrooms, drained (my family does not eat these)
1/2 to 3/4 Cup of water
3 beef bouillon cubes
2 TBLS ketchup (you can skip this, but I didn’t even though the thought of ketchup in a classy dish just somehow seems to spoil it–but it works)
1/2 Cup of water
2 TBLS of flour
1 and 1/2 Cups of sour cream
1/2 Cup sherry
8-10 oz of cooked noodles

Cut meat cross grain into 3/4″ cubes.
 
Melt 3 TBLS of butter in a 12″ skillet.
Cook 1/2 of the onions, mushrooms, and garlic until tender.
Add 1 and 1/4lbs of beef.  Brown meat on high heat quickly, first one side, then the flip side.  Don’t cook, just sear to seal in juices.
Remove meat and juices from pan to a dish and then repeat the process beginning with melting the butter again for the rest of the meat.

When all the meat has been browned, put it back in the 12″ skillet with the juices.  Stir in 1/2 Cup of water. Add the bouillon cubes and ketchup.
Reduce the heat and cover the skillet, simmering for 15 minutes (I had the cover part way off to help burn off the water and then I stirred the meat around to absorb the browned flavors in the pan.)

While the meat simmers, prepare the noodles.

Just before the 15 minutes are up, mix 2 TBLS of flour and 1/2 Cup of water ( I shake them together in a closed container).  Add the mixture to the meat, heat to boiling, stirring constantly for 1 min.  Make sure the juices get absorbed by the flour.  If not, add a couple more TBLS of flour and stir them in.

If there seems to be a lot of juice or butter still in the pan, carefully drain it off.  You want the meat fairly dry, yet still moist before adding the sour cream.
Stir in the sour cream gradually.  Have the heat on low.
Once the sour cream is blended throughout the meat and its juices, gradually add the sherry until the sauce is a creamy but not runny consistency.

Serve over noodles.

Heavenly~according to Hubby.

     “However, let each man of you (without exception) love his wife as (being in a sense) his very own self, and let the wife see that she respects and reverences her husband–that she notices him, regards him, honors him, prefers him, venerates and esteems him, and that she defers to him, praises him, and loves and admires him exceedingly.” Ephesians 5:33 Amplified

     When expounded on like that, it’s a pretty tall order~.