Heat 1 tablespoon olive oil in your large skillet or Dutch oven over medium-high heat. Add the beef strips in a single layer and sear until browned on all sides, about 3-4 minutes. Remove the beef from the pot and set aside.
In the same pot, add the diced onion and cook until translucent, around 3 minutes. Add the minced garlic and sliced mushrooms, cooking until the mushrooms release their moisture and start to brown, about 5 minutes.
Sprinkle 1 teaspoon paprika and 1 teaspoon dried thyme over the vegetables, stirring to combine. Pour in 4 cups of beef broth and scrape the bottom of the pot to deglaze, lifting any browned bits for extra flavor.
Add 12 ounces of egg noodles to the pot. Return the browned beef strips to the skillet. Bring the mixture to a boil, then reduce heat to medium-low and simmer, uncovered, until noodles are tender and most of the liquid is absorbed, about 8-10 minutes. Stir occasionally to prevent sticking.
Turn off the heat and stir in 1 cup of sour cream until the sauce is creamy and smooth. Taste and season with additional salt and pepper if needed.
Sprinkle freshly chopped parsley over the top for a pop of color and fresh flavor. Serve immediately and enjoy the comforting goodness!