Baked Sunday Mornings: Brown Sugar Oatmeal Whoopie Pies with Maple Marshmallow Filling

Truth be told, National Maple Syrup Day was not really on my radar as part of the Fall/Winter holiday season. But alas, it is apparently a thing, celebrated on December 17th in honor of that sweet, magical serum derived from maple trees. I don’t remember eating it much growing up (and if I did, I’m sure it wasn’t the real stuff), so I think my first exposure to it was when I lived in Boston in college. New England being the primary producer of American maple syrup meant that it was much more ubiquitous in Massachusetts than in the suburbs of San Francisco.

To celebrate such a momentous day, Baked Occasions features these Brown Sugar Oatmeal Whoopies with Maple Marshmallow Filling, which might be the longest title of a recipe ever, and which is incidentally our Baked Sunday Mornings recipe for this week! When our group tested the recipes for the book, this was one of the ones that I was lucky to be assigned. What’s not to like about two soft maple-y oatmeal-y cakey cookies sandwiching a layer of maple marshmallow? It was one of my favorite recipes to test and eat, and in my opinion it needed no changes at the time.

The cookies are extremely easy to make– no mixer needed. You’ll start by pulsing the oats in a food processor to make a combination of oat pieces and powder, which you’ll then combine with the flour, baking powder, baking soda, salt, and cinnamon.

In another bowl, whisk the dark brown sugar and canola oil to form a mixture that resembles wet sand, to which you’ll add the eggs, yogurt, sour cream, maple syrup, and maple extract. A word about maple extract– it is delicious stuff! I had to do a bit of hunting when I was testing the recipe, since *pure* maple extract is not easy to locate in a typical grocery store. (The recipe specifies not to use an imitation extract or flavoring.) What’s a girl to do? To the Amazons! Of a few brands that I found, I chose OliveNation, and I was on my merry way. It will keep a long time, and you can use it to bump up the maple flavor in any maple-centric dish. It’s a deep, dark brown-black hue– much darker than vanilla.

Anyway, you’ll fold the dry ingredients into the wet until no flour streaks remain, and refrigerate the batter for at least 20 minutes (I think mine was in for about 35 minutes), during which it will firm up enough to be scooped.

Now, the recipe says to drop heaping tablespoonfuls onto the cookie sheets; however, my pies spread HUGE in the oven! If you want mini pies (as I intended), use a melon baller-sized scoop. The scoop that I used holds about a tablespoon, and they grew to 3″ across. Crucial here is spacing the batter mounds several inches apart to accommodate the spreading. They will puff waaaay up, then sink and flatten. (I would have liked them to stay puffed!) My whoopies baked for exactly 12 minutes– enough to set the top and edges, but maintain a soft interior.

While the whoopies cool, you’ll make the marshmallow filling. This is a true marshmallow recipe, i.e. it contains gelatin, whereas many “marshmallow” creams are more of a meringue made with sugar and egg whites only.

You’ll start by blooming the gelatin in cold water to soften the granules. Meanwhile, beat the egg whites in a stand mixer, then melt the sugar with water and bring it to 235°F, at which time you’ll stir in the gelatin. It bubbled up significantly for several seconds. Slowly stream the sugar/gelatin mixture into the egg whites– it’s important to pour right against the edge of the bowl to avoid getting it on the whisk and flinging it all over the mixer bowl.

The marshmallow is supposed to beat on high for about 10 minutes to reach stiff peaks, but mine took maybe half that time. Finally, you’ll add the maple extract for flavor and color– I added the full 3 teaspoons, as I found that 2 teaspoons imparted only a subtle maple flavor. (And I wanted serious maple flavor, people.)

My marshmallow mixture was silky smooth and light as air– off to the pastry bag it went! Pipe spirals onto half of the whoopie cookies and match them up with similarly sized tops. My only regret is not filling the pies more– they looked a little flat and anemic. I ended up with A LOT of extra filling.

The last step is the trickiest part– toasting the edges of the marshmallow! A few minor burns were sustained as I tried to simultaneously torch the pies with my kitchen torch in one hand, and hold/turn the pies in the other. That thin layer of marshmallow is a narrow target, and more than once I felt the heat of the flame on my fingertips! Perhaps this wouldn’t have been so difficult if my pies were filled with a thicker layer of marshmallow…

The recipe yielded way more pies than expected (24 assembled pies vs. the anticipated 15-17), and when I looked back at my notes from testing, the same thing had happened that time.

Did I like these as much as I remembered? Not quite. They were okay, but more marshmallow would definitely have helped. Also, I found the cookies to be really chewy, but not in a pleasant way– I might break down the oats further next time. The overall maple flavor was nice– I am definitely a fan of that maple extract!

With a couple of tweaks, I think these would be much better; I would probably make them again. The warm maple and brown sugar flavors are lovely for the holidays, that much is certain. If you want to pay proper homage to maple syrup, you can find the recipe for Brown Sugar Oatmeal Whoopies with Maple Marshmallow Filling over at Baked Sunday Mornings. See how my fellow bakers liked them while you’re there. This recipe concludes our BSM baking for 2015– how did another year fly by?? I thank you for reading, and I wish everyone a warm, loving, and dessert-filled holiday season! 😀

© Dafna Adler & Stellina Sweets, 2015.