Place a large pot of water over high heat and bring to a boil to cook egg noodles.
While the water is coming to a boil, place a large skillet over medium-high heat and add ground beef. Cook the beef approximately 6–8 minutes, breaking the meat into small chunks as it browns.
When it has nearly browned and only a bit of pink remains, add onion and garlic. Cook an additional 3–4 minutes until onion has softened.
Drain excess grease from beef and return the skillet to heat. Sprinkle with flour and stir to combine. Once the flour is completely absorbed, add beef broth and bouillon, stirring to combine.
Add mushrooms and bring liquid to a boil. Reduce heat to medium-low and simmer, stirring occasionally, for 15 minutes or until the sauce has thickened substantially.
While sauce is simmering, add egg noodles to boiling water and cook according to package instructions. Drain noodles into a colander but do not rinse. Set aside until the sauce has finished cooking.
Once the sauce has simmered until nice and thick, remove from heat and stir in sour cream. Season to taste with salt and plenty of fresh cracked black pepper then spoon over cooked egg noodles. Enjoy!
Notes
To prevent noodles from sticking together after cooking, toss them in a bit of melted butter.