Classic Whoopie Pies

While testing this recipe, I took some to our friends’ house to share. Mere moments after arriving, their two kids both had a Whoopie Pie in each hand and were chowing down. I guess we had a hit on our hands!

Typically, I do not prefer a cakey texture in my desserts. I prefer my cookies to be chewy (like my Bakery Style Chocolate Chip Cookies) and my brownies to be fudgy (like my go-to Brownie Recipe) … but there’s something about a Whoopie Pie that just makes me feel like a kid again.

They’re slightly chewy around the edges but soft and cakey throughout. Not to mention each ‘pie’ is filled with thick, luscious marshmallow fluff frosting.

What’s not to love about that?

Sprinkle of Science

How to Make Whoopie Pies

The Cocoa Powder

I recommend using Dutch-process cocoa because it provides a deep color, more moisture, and a flavor that I think complements the marshmallow filling perfectly. But why am I using Dutch-process cocoa with baking soda for this recipe? Shouldn’t it be baking powder?

Dutch-process cocoa has more fat than most grocery store natural/unsweetened cocoa powder products, which is what we want for flavor and moisture in this specific recipe. The buttermilk in this recipe activates the baking soda.

If you must use natural cocoa powder, go ahead – just note that your Whoopie Pies may be lighter in color and slightly dryer in texture. You can learn more about the differences between cocoa powders here.

You can typically find Dutch-process cocoa at grocery stores or many gourmet food stores like Sur la Table, Williams Sonoma, or Penzeys. I actually order a big container on Amazon because it’s such a great value!

Tip: Measure Your Ingredients Correctly!

If you add too much flour or cocoa powder, you may end up with dense, hard Whoopie Pies. This happens super easily when measuring with cups. I highly recommend using a digital kitchen scale, but if you don’t have one, use the spoon and level method instead.

The Buttermilk

Buttermilk works best in this recipe to provide rich and tender ‘cakes.’ We need it not only for flavor and moisture, but to help the leavening action by activating the baking soda. I don’t recommend using a buttermilk substitute. You can learn more about the science of buttermilk, and see baked goods made with buttermilk substitutes, in my Buttermilk 101 article.

The Butter

Always use unsalted butter in baking. It’s important that your butter is at a cool room temperature. Your sticks of butter should give slightly when pressed with your finger but still hold its shape. To be precise, your butter should be 67°F, or even a couple degrees cooler if your kitchen is very warm.

The Sugar

We are using dark brown sugar for additional moisture, but you can use light brown instead if needed. Whatever you do, don’t reduce the sugar. Learn about everything sugar does in baking here.

The Egg

We just need one large egg for this recipe, at room temperature. Don’t use extra large eggs or medium eggs, as this will alter the chemistry of the recipe.

The Marshmallow Creme

This is an easy, quick way to make this filling full of marshmallow flavor, without having to make your own marshmallow or mess with melting down regular marshmallows. You’ll need either one of the larger 13-ounce containers or two of the smaller 7-ounce ones. Marshmallow Creme or Marshmallow Fluff work here. Marshmallow creme has a slightly thinner consistency than fluff, so you may need to add a bit more powdered sugar to sufficiently thicken it up.