Preheat oven to 165 °C.
In a large dutch oven, heat the olive oil over a medium-high heat and brown the beef on all sides. Best down in batches. Remove the beef and set it aside.
In the same pot, add the onions and cook for about 5 minutes, until softened. Add the garlic and mushrooms and cook for a further 5 minutes.
Return the beef to the pan. Add the carrots, beef stock, red wine, diced tomatoes, tomato paste, herbs, salt, and pepper. Stir to combine.
Bring the mixture to a simmer before covering and transferring to the oven. Cook for 2 ½ hours.
In a small bowl, combine the flour with 3 tablespoons of water to make a slurry. Add this into the beef mixture along with the sour cream, stir, and then cook for an additional 30 minutes.
Remove the bay leaves and then serve with mashed potato and garnished with parsley.