Place beef cubes and flour in a large, resealable plastic bag. Shake to coat all pieces.
Heat 1 Tbsp oil in large saucepan or Dutch oven over medium-high heat. Add some of the beef cubes and brown on all sides. Remove browned beef and place in large bowl. Continue browning remaining beef cubes with remaining oil. Some additional oil may be needed. Remove all beef cubes from saucepan.
Reduce heat to medium. Add onions to saucepan, adding some additional oil if necessary. Cook about 3 to 4 minutes or until tender, stirring occasionally. Add garlic; cook another minute or release the aroma of the garlic (do not allow garlic to color). Add beef cubes, carrots, broth, beer, raisins, tomato paste, caraway seed, bay leaf and thyme to saucepan; stir well.
Cook uncovered, over low heat, stirring occasionally, for 1 1/2 to 2 hours or until beef is tender. Remove from heat; discard bay leaf and thyme sprigs. Sprinkle chocolate over stew; stir to combine (the chocolate becomes part of the sauce).
Serve immediately with a warm, hearty bread, if desired.Servings: 4 to 6