Trim beef cubes, cutting off fat as much as desired.
In heavy frying pan, heat the oil over medium-high heat and brown half of beef cubes, turning several times so it’s well browned on all sides.
Put browned beef in crockpot and brown the rest of beef, adding more oil if needed. Put second batch of browned beef cubes in crockpot.
Add beef broth (or homemade beef stock) to frying pan, scraping up any browned bits from the bottom of the pan, and simmer until beef broth is reduced to ¾ cup.
While beef is browning, cut the garlic into slices and cut the Kalamata Olives in half.
Measure stock to see when it's reduced to ¾ cup and add reduced broth to crockpot.
Add garlic and olives to crockpot along with rinsed capers, bay leaves, oregano, canned tomatoes and juice, tomato sauce, tomato paste (if using), red wine vinegar, and pepper.
Cook on high for about 4 hours or a little longer, until meat is tender and flavors are well blended. (This could also be cooked in the slow cooker on low for 8-9 hours.)
Serve hot.
