in a large pot mix olive oil and butter. When melted, add beef, salt and pepper and Brown meat on all sides. Remove meat and set aside.
Add the tomato paste, onion, celery and carrots to the pot and cook about 8 to 9 minutes. Add the wine and the broth and scrape bits off the bottom. Bring mixture to a boil, then return beef to pot, add bay leaves and cover. Reduce heat to simmer and cook for three hours or until meat is tender.
Remove Bay leaf and set the beef on a platter. Puree remaining liquid and vegetables to form a sauce. Taste for salt and pepper and serve sauce with beef. Makes 4 to 6 servings