In a large skillet over medium-high heat, add the olive oil and then the diced onion. Cook the onion until translucent, about 2-3 minutes. Add the garlic and cook until fragrant, about 1 minute.
Add the ground beef, breaking it up as it cooks. Cook the beef until no longer pink, about 5 minutes.
Next, add the beef broth, worchestershire sauce, egg noodles, smoked paprika, and 1 tsp each of salt and pepper. Give it a good stir and then cover it and reduce the heat to medium. Let it simmer for about 18 minutes until the egg noodles are cooked, stir halfway through.
While the noodles are cooking, grab a small bowl and combine the cornstarch and milk and whisk with a fork until there are no lumps. Set aside.
When the noodles are cooked, add the milk-cornstarch mixture and let it simmer until the sauce has thickened, about 2-3 minutes. Then lower the heat to low and add the sour cream. Mix until the sour cream is fully incorporated.
Add the chopped parsley and taste for seasoning. Add more salt and pepper if necessary. Enjoy!