I am thinking of making these as part of a box of Christmas cookies that I will give as gifts, but I do not know if the Mouselline recipe used for the filling (has more sugar that regular) can be kept at room temperature for more than 1 day.  Does anyone have experience with this?  I do miss the storage guidelines of TCB although I know RHC has guidelines in the introduction pages, but I prefer the more specific details of TCB.

Sherrie, I haven’t tried storing the whoopie pies at room temp, but I would be more worried about the cake drying out than the mousseline deteriorating if it is only a day or two.  When I wrapped mine in plastic wrap, some of the crust stuck to the plastic when I unwrapped them (stored in the fridge).  Like most butter cakes, these were the best within a day of baking.

I realize it would be safest to get Rose’s tested guidelines for keeping, but I do think it would be very similar to mousseline.  Adding powdered sugar and butter to moussline probably won’t shorten keeping qualities.  Perhaps a little label could be placed on the w. pie’s plastic wrap that says to freeze it if not eating soon?

Good luck!

I had the same experience with the whoppee pie.  The cream would be fine for a couple of days at room temp…the problem is the cake.  The crust stuck to the plate, to the plastic wrap, to everything, actually.  I loved them and had great fun with them…but they are tricky to keep.