Prepare the beef. Slice the steak against the grain into ¼-inch thick strips, discarding any excess fat. Season with salt and pepper to taste.
1½ pounds ribeye steak, Kosher salt and freshly ground black pepper
In a large skillet set over high heat, add 1 tablespoon olive oil. Working in batches, sear the strips of beef for 1-2 minutes on each side, then transfer it to a plate. Repeat with the remaining meat, adding more olive oil as needed. Once all of the beef is seared, set aside.
2 tablespoons olive oil
In the same skillet, melt 3 tablespoons of butter. Add the mushrooms and onions and cook for 4-5 minutes, until the onions soften and the mushrooms have released all of their liquid and begin to brown.
5 tablespoons unsalted butter, 1 pound cremini mushrooms, 1 yellow onion
Add garlic and sauté for 30 seconds, until fragrant.
3 cloves garlic
Pour in the wine and deglaze the pan, then bring it to a boil. Once boiling, reduce the heat to medium and simmer until nearly evaporated, 4-5 minutes.
½ cup dry white wine
Sprinkle the flour over the onion-mushroom mixture, stirring until incorporated. Fold in the sour cream, Dijon, Worcestershire sauce, and Italian seasoning, stirring until everything is fully incorporated.
¼ cup all-purpose flour, ½ cup sour cream, 1 tablespoon Dijon mustard, 1 tablespoon Worcestershire sauce, ½ tablespoon Italian seasoning
Pour in the broth and stir until smooth, then bring the mixture to a simmer for about 5 minutes, stirring often, until thickened.
1¾ cups low-sodium beef broth
While the sauce simmers, prepare the noodles according to the package instructions. Drain and toss the noodles with 2 tablespoons of butter and cracked black pepper.
10 ounces dry egg noodles
Return the meat and any juices back into the sauce and heat until warmed through.
Stir in fresh parsley and serve over noodles.
Fresh parsley