Melt the butter in a large skillet over medium high heat. Add the sliced mushrooms and cook until they are softened, abut 5 minutes.
2 tablespoons butter, 16 ounces sliced mushrooms
Add the beef broth, onion soup mix, thyme, pepper, and noodles to the skillet. Cover and cook for about 6-7 minutes, until the noodles are just about done.
3 cups beef broth, 1 ounce onion soup mix, ½ teaspoon pepper, ½ teaspoon thyme, 4 cups wide noodles
Stir the flour into the sour cream, then add it into the skillet. Stir until it incorporates into the sauce.
1 tablespoon flour, 1 cup sour cream
Cook for another 5 minutes until the sauce somewhat thickens.
Add the meatballs and continue to cook until they are warmed through.
18-24 cooked meatballs
Garnish with chopped parsley if desired.
fresh parsley
Video
Notes
You can substitute olive oil for the butter if desired.
You will speed up the cooking time if you defrost the meatballs prior to adding them into the skillet.
You can use other types of noodles, just adjust the cooking time so that the noodles are not overcooked.
The sauce will thicken more upon standing.
If you are concerned about salt content or the dish tasting too salty, use unsalted butter and/or low sodium broth and/or low sodium onion soup mix.