Brown ground beef and drain off fat. Let it cool for a few minutes then add Worcestershire sauce to the meat. Leave on low heat.
In a smaller pan, melt butter then add diced onion and garlic. Cook on a medium heat until the butter begins to brown then turn the heat up to medium high and stir while the onion and garlic browns to taste. Add the onion mix to the meat. Add dill to meat and onions. Turn the heat up to medium, so it simmers a little but doesn't boil or burn.
Cook (medium heat) sliced mushrooms in the pan that's still buttery from the onion and garlic. Mushrooms are done when they've changed color and shrunk a lot. Add the mushrooms to the meat mix. Add nutmeg and beef gravy; simmer.
Boil egg noodles according to package directions.
Either mix the sour cream in with the meat sauce or serve it on the side to accommodate lactose intolerant diners. Serve the sauce over the egg noodles.