Place beef in a 4-quart slow cooker. Crush caraway seeds with the bottom of a saucepan or meat tenderizer. Transfer to a small bowl and stir in paprika, salt and pepper. Sprinkle the beef with the spice mixture and toss to coat well. Top with onion and bell pepper
Combine tomatoes, broth, Worcestershire sauce and garlic in a medium saucepan; bring to a simmer. Pour over beef and vegetables. (You can skip this step and just add the ingredients to the slow cooker). Place bay leaves on top. Cover and cook until the beef is very tender, 4-1/2 to 5 hours on high or 7 to 7-1/2 hours on low.
Discard the boy leaves. Add the cornstarch mixture to the stew and cook on high, stirring 2 or 3 times, until slightly thickened, 10 to 15 minutes.