Preheat oven to 350º F. Generously salt and pepper the beef. 

Pour 2 tablespoons of oil into dutch oven and heat until hot on medium heat. Once oil is hot, sear the meat on all sides until each side is browned, about 3-4 minutes on each side. 

Add in the onions and sauté for about 4 minutes to soften slightly adding more oil if needed. Add garlic and sauté 1 minute. 

Stir in the carrots, oregano, and thyme. Pour in the beef stock. (Beef stock should cover most of the meat (or all). If it does not turn meat every 30 minutes while cooking so it doesn’t dry out.)

Cover with a tight-fitting lid and bake for 3 hours or until meat can be pulled apart with a fork very easily. (An internal temperature of over 200°F for fall apart tender beef.)

When the roast is tender, cook the mushrooms. Place oil and butter into a non-stick pan. Once butter is melted and oil is hot add the mushrooms. Sauté until mushrooms are tender.  

Add the mushrooms to the dutch oven with the roast and other vegetables. Cover and bake for 15 minutes more.

Gravy
Remove the roast from the oven. Remove the meat to a plate and cover with foil. Use a slotted spoon to remove the carrots, onions and mushrooms to a large serving bowl and cover with foil. There should be about 3 cups beef stock left in the pan.

Whisk together flour and water until smooth. Whisk into beef stock. Add in the beef flavored Better Than Bouillon. Whisking until dissolved. 

Place dutch oven on the stove top and cook the gravy on medium heat until it comes to a boil. Simmer for about 2-3 minutes or until thickened.

Remove from heat and whisk in the heavy cream until blended. Add salt and pepper to taste.   

ServingSlice the roast and serve it with the carrots, onions, and mushrooms over mashed potatoes covered with gravy.