Rinse beef and pat dry. Sprinkle generously with black pepper. Melt butter or heat olive oil in a large non-stick skillet over high heat. Add beef and brown on all sides, 6 to 8 minutes total.
Meanwhile, place the carrots, celery, onions, garlic, thyme peppercorns, and bay leaf in a 4 1/2 qt or larger crock pot. Mix to combine. Set beef and any juices over vegetables.
In a small bowl, mix tomato paste and wine. Pour over meat and vegetables.
Cover and cook until beef is very tender when pierced, 8-9 hours on low and 5-6 hours on high. If possible, turn meat over, halfway through cooking.
With 2 slotted spoons, transfer meat to a serving platter, keep warm. Skim and discard any fat from cooking liquid. Turn cooker to high. In a small bowl combine cornstarch with 1 1/2 tbs water, pour into cooker and stir often until sauce is thickened, 10 -15 minutes.
With slotted spoon, arrange vegetables evenly over meat in platter, pour sauce over meat and garnish with chopped parsley; serve hot.