Cut roast into 1 1/2 inch bite size chunks and place them in a gallon size resealable bag or other airtight container. Add flour, salt, and pepper. Shake bag until the meat is coated with flour.
Heat olive oil in a large heavy bottom skillet or pot. Add coated meat and brown each piece on all sides.
While meat is browning, cut potatoes and carrots and place both in the bottom of a crock pot. When meat is browned, layer the meat on top of the potatoes and carrots and leave remaining juices in the skillet.
Return the skillet to the stovetop and add butter. Melt the butter on medium-high heat, then saute onions and garlic. Stir in beef broth, tomato paste, red wine vinegar, and Worcestershire sauce. In a small cup, combine cornstarch and cold water. Mix until smooth then add to the liquid mixture in the skillet. This will thicken the liquid. Pour all the contents of the skillet over the meat and vegetables in the crock pot. Add thyme, parsley flakes, and bay leaves.
Cook on low for 7-8 hours or on high for approximately 4 hours. 30 minutes before serving check the taste of the broth and add salt, pepper, or seasonings as needed. Allow to cook for another 30 minutes after adding seasonings.
Remove bay leaves before serving. Garnish with fresh parsley.