Preheat large deep skillet or dutch oven to medium-high. Put 1 - 2 tablespoons of oil to coat. Place beef, onions, garlic, and mushrooms in the skillet, then cover beef with water and add the beef boullion. Cover and simmer on low-medium heat for at least 30 minutes.
Once beef is cooked through and mushrooms and onions soft, add 1 block of cream cheese, stir, and bring back to steady simmer. Simmer UNCOVERED for another 15 - 30 minutes on low to medium heat, until sauce has reduced by half. Stir in sour cream.
Once fully incorporated and thickened, remove from heat and serve over wide egg noodles, pasta or gnocchi.