Heat the oil in a large skillet over medium heat. Toss the beef with the flour, then add the flour to the skillet. Cook, stirring frequently, until the meat is mostly browned. Add the onion, garlic, and tomato paste, and cook for 5 minutes, or until the onions are tender. Pour the mixture into the crock pot. Add 1 cup of beef broth to the hot skillet, and stir to loosen the browned bits from the bottom of the pan. Pour the broth into the crock pot.