Heat 1 tablespoon oil in a 12-inch skillet over medium-high heat. Add the beef and cook until well browned, stirring often. Remove the beef from the skillet. Pour off any fat. Heat the remaining oil in the skillet over medium heat. Add the peppers and onion and cook until the vegetables are tender, stirring occasionally. Add the garlic and oregano to the skillet and cook and stir for 1 minute. Return the beef to the skillet. Stir in the concentrated broth and water and cook until the beef is cooked through.