Dust the cubed chuck with some kosher salt (maybe a tsp).
In a pot, saute the onions in about 2 tbl of whatever fat (oil) you chose above (medium heat). When they are soft and translucent, add the beef and paprika; stir, reduce heat to low for about an hour. The beef needs time to tenderize, which it will do in its own juices.
When the beef is fairly tender, add bay leaves, beef stock (pre-heating this may speed things up a little), potatoes (if you are using them), and black pepper. Simmer, uncovered, on med-low until liquid cooks down, potatoes are tender, and beef is approaching the fall-apart stage. Add salt as necessary (be careful – the beef stock will already have somewhere between some and a lot). If you have a buildup of dark stuff on the bottom of the pot, be sure to gently scrape it up – that’s the fond, and there’s lots of flavor in there!
The sour cream can either be mixed in toward the end of the cooking time (I’d suggest that you act like you are tempering it and pre-mix it with a little of the broth to avoid clumping, then mix that into the main pot), or served in dollops on top of the goulash. Or, you can leave it out altogether. The amount of sour cream might relate to the amount of paprika you chose to use; the more paprika, the more likely you’ll need to cut it with a little sour cream.
Remove the bay leaves. Don’t ever eat the bay leaves.
Put the goulash on top of the noodles, and enjoy!