Although the results will not be identical, if you have leftover chocolate soufflés you can enjoy them later. Wrap each with plastic wrap or foil and refrigerate for about 2 to 3 days. Take them out of the fridge 30 to 60 minutes before you want to reheat them so they aren't ice cold. Then reheat them in an oven or toaster oven around 350°F. They should rise again (but not as much as day 1) and be warm in the center before serving.