Preheat oven to 350ºF. Line 2 cookie sheets with parchment paper.

Cream butter until it is light. Add brown sugar and mix until it’s incorporated and light. Then add the egg yolks, one at a time, mixing well after each addition. Add pumpkin and vanilla, and mix well.

Slowly add dry ingredients (helps to first mix them all together in another bowl or on a sheet of wax paper), and mix until thoroughly combined. Be careful not to over mix or the cookies will be tough.

Drop batter by tablespoon about 1 inch apart on the prepared cookie sheets. (For especially neat Whoopie Pies, pipe them using a 1/2″ tip.) Bake until they are puffed and spring back when touched, 10 to 12 minutes. Transfer the cookies to a cooling rack.

Make the filling: Whisk the butter until light, then whisk in 10x sugar until light and fluffy. Add salt and mix well, then whisk in vanilla. Add the egg white, whisking vigorously. The mixture will break and separate, but continue whisking vigorously until it comes back together and forms a smooth cream. Then whisk in the milk.

When the cookies are completely cool, spread one cookie with a thin layer of filling and top it with another cookie to make each Whoopie Pie. Continue with the remaining cookies and filling. Store the cookies in an airtight container. They will keep for at least a week if you can keep anyone from finding them…

Yield: 32 Whoopie Pies

Note: Because I like to use fresh ground whole wheat whenever possible, I substitute soft whole wheat flour (sometimes called whole wheat pastry flour) for at least half the flour called for in the recipe. It can make for a denser cookie — still tastes great (I think it adds more flavor, in fact) but if you’re not used to whole grain baking, you may want to stick with 100% all-purpose flour, bleached or unbleached.