If you are invited to a dinner party, it is often a good idea to bring something along. The question is what might be welcomed, and what might be embarrassing. You can ask, but too often the host or hostess will suggest you bring nothing. That is just a polite response, and that response may not be something you should follow.
You do have several options, but one is certainly not the main course. The main course is the part of the meal that sets the tone for the event, and that should be left to the host or hostess. It is always inappropriate to bring a second main course, especially if it upstages the one chosen by the host or hostess.