After freshening up, grab dinner at a local bistro. Here you'll find the classics: onion soup, steak frites, and duck confit. You can use the French site LaFourchette to get local insight into the best places and make a reservation online.
After dinner, walk it off by heading to the Eiffel Tower. There are fewer crowds at night, making it much more enjoyable (and less time-consuming) to walk up to the top platform. If you time it right, you'll be on the tower as it sparkles. The light show happens on the hour and lasts five minutes. The last admission to walk up the Eiffel Tower is at midnight during mid-June to early September and 11 p.m. the rest of the year.