Preheat your pan over high heat and add oil. Add beef and cook, stirring constantly, for 5-6 minutes, or until liquid evaporates and meat is browned. Remove meat from the pan and set aside.

Add butter, mushrooms, onions and garlic into the pan, season them with salt and cook over medium-high heat until the vegetables begin to develop some color. Stir in flour and cook for about 1 minute.

Stir in 3 cups of stock and add your beef. Bring to a simmer, cover and cook on low heat for about 1 hour or until the beef is tender and the sauce has thickened. Stir in sour cream, chives and serve over sautéed potatoes.