For the filling in these cinnamon-and-allspice whoopie pies, a caramel sauce is folded into the buttercream. A hint of salt is mixed with sugar that surrounds the edges, to slightly offset the sweetness.
We split the batches of meringue to tint them separately with brown sugar and white sugar, then we tinted some of the latter pink, too. For uniform circles, trace a 2-inch bowl or a round cookie cutter on the back side of the parchment. Be sure to have everything ready before you start mixing the meringues.
Pumpkin puree works as the go-to here, but if craving something different, try a winter squash puree. For the gluten-averse, this pie features a rich, rice-cereal crust. Blind-baking it before filling keeps it crisp.