These homemade gluten-free whoopie pies are made with a moist chocolate cake and have a delicious, oh-so creamy marshmallow or vanilla buttercream filling. This recipe is easy to make and the perfect treat.
What is a Whoopie Pie?
A whoopie pie is simply a sandwich made with small rounds of firm rich, chocolate cake with a creamy filling. The traditional filling is marshmallow cream but buttercream makes an excellent substitute. A muffin top pan or whoopie pie pan is the perfect tool for making the chocolate rounds.
Chocolate Cake Ingredients
Gluten-free flour – The trend in gluten-free baking has moved to all-in-one wheat flour replacements. So I developed this recipe using King Arthur Measure for Measure Flour. King Arthur is widely available and the most affordable option I have used (relative to the gluten-free world) Its is certified gluten-free. Be sure to check out my collection of King Arthur Gluten-Free Flour recipes.
Cup4Cup (contains milk powder) and Pamela’s All Purpose Artisan Blend will work well too (certified gluten-free). I did not test with Bob’s Red Mill 1 to 1 (not certified GF) since I have had sensitivity issues with their products.
Cocoa Powder – This recipe has equal parts flour and cocoa powder for a strong, dark chocolate flavor. Ghirardelli used to be my go-to, but their products now contain a wheat warning. Hershey’s Dutch process cocoa powder works well in this recipe and has no wheat warnings.
I use dairy-free milk substitutes – almond, coconut, oat, soy will all work. Just be sure to use an unsweetened one.
I prefer oil over butter in my cakes. It does a much better job of adding a rich, moist texture to gluten-free cakes. Light olive oil, sunflower, avocado, safflower, canola or any neutral vegetable oil will work.
Mixing the Cake Batter
More than many cake batters, this one will develop air pockets very easily. Too much air will make these little cake dry and will create bubbly tops. A lot of chocolate cake recipes solve this problem by adding hot water to the batter. I just don’t like this idea when there are raw eggs involved. So, follow the method in the recipe card below for recipe that mixes up in just one bowl!
Whoopie Pie Filling
Marshmallow filling is the traditional whoopie pie filling and makes such a fun treat. Unfortunately the store bought marshmallow creams like Fluff are too runny for a whoopie pie.
It takes only little extra time to make from scratch and is well worth it for this pretty, white pillowy filling. This filling is a bit runny right after mixing. I suggest making before the cakes and let it sit uncovered. It will firm up a little, making it a better consistency for filling.
Buttercream frosting is the preferred filling in my house so I’ve included my favorite vanilla buttercream frosting recipe. For more frosting options check out my pipeable cream cheese frosting. vegan chocolate cream cheese frosting, 2-ingredient vegan chocolate frosting or even my unusual, yet delicious and creamy sweet potato frosting which is sweetened only with maple syrup.
You can also add flavored extracts or syrups to the vanilla buttercream, like mint extract or creme de menthe (in these whoopie pies above) or orange extract, which is amazing with chocolate. Add 1-2 tsps of extracts.
Baking the Cakes
You will need muffin top pan(s) or a whoopie pie pan (same thing) to make the cake portion of this recipe. The wells are 3″ wide by 1/2″ high. I have seen other whoopie pie pans that are 1 – 1.5″ high. In my opinion, that is too tall. I have a FULL cupboard, but luckily these pans don’t take up a lot of space and they’re great for making toaster corn muffin tops too.
The recipe makes 10 whoopie pies which requires 20 little cakes. Muffin top pans come in 6 or 12. I have a 12, so I did it in 2 batches. Since the cakes bake up in 10 minutes and the pan cools quickly, this will work. Otherwise, get yourself 2 of these pans and bake them all at once!
And, YES, these little cakes bake at 325°F, not the usual 350°F baking temp. It works best for this chocolate cake.
Gluten-Free Whoopie Pies with Marshmallow Filling
Gluten-Free Chocolate Cake
- 3/4 unsweetened Dutch process cocoa powder `
- 2/3 c unsweetened dairy-free milk room temperature
- 2/3 c oil light olive, sunflower, avocado, canola
- 1 c sugar
- 3 large eggs room temperature
- 1 tsp vanilla extract or powder
- 3/4 c gluten-free flour blend*
- 1/2 tsp baking powder
- 1/8 tsp salt
Vanilla Buttercream Filling
- 1 stick 4oz unsalted butter, room temperature
- 1 1/2 c powdered sugar
- 1 tsp vanilla extract or powder vanilla powder linked above is highly recommended as it will retain the bright white color of the cream
- 2 tps milk or milk substitute
- 2 large egg whites room temperature
- 1/4 c + 2 Tbsps sugar NOT powdered
- 3 Tbsps light corn syrup
- 1/2 tsp vanilla extract
- If using the marshmallow filling, I recommend making it before the cakes. It needs a little time to firm up. Instuctions below.You will need a muffin top/whoopie pie pan (linked above).
Make the Chocolate Cakes
- Pre-heat the oven to 325°F.
- If the eggs are cold, place in a bowl of warm water while preparing the other ingredients.
- Sift the cocoa powder into a large mixing bowl.
- Heat the milk and oil until warm to the touch. I heat them in a glass measuring cup in the microwave for about 1 minute.
- Add the milk & oil to the cocoa powder and stir with a whisk or electric mixer for 30 seconds. The mixture might be a little lumpy, but it will smooth out when the eggs are added.
- Add the sugar, eggs and vanilla and beat until smooth.
- Sift in the flour, baking powder and salt and beat until smooth.
- Grease the whoopie pie pan. Fill each well with 3 Tbsps batter. The cookie scoop linked above is just the right size.
- Smooth the tops and spread evenly to the edges. Gently, shake the pan side to side and forward and back to level the batter,
- Bake 10-12 minutes or until the top is set and bounces back from a gentle tap.
- Cool in the pan for 5 minutes, then transfer to a wire rack to cool completely. These will need to cool for about an hour before handling or the top is too sticky.
Make the Filling – Either Buttercream OR Marshmallow Filling
- This buttercream filling can be made ahead of time. If using within 24 hours, leave at room temp, otherwise, refrigerate and pull it out about 2 hours before using.
- If your powdered sugar is very lumpy, I suggest sifting it, especially in humid climates. I use C&H and rarely sift, and get smooth creamy results.
- Using an electric mixer, beat the butter for 30 seconds until creamy.
- Add half of the powdered sugar and beat on low until incorporated. Add the remaining powdered sugar and beat on low until incorporated.
- Scrape down the sides and bottom of the bowl. Add the milk and vanilla and beat on high for 15- 20 seconds.
- See above for flavor options or more frosting recipes.
- For easiest assembly, place the buttercream in a pastry piping bag fitted with a tip.
- This marshmallow filling is a bit runny right after mixing. It works best if it sits uncovered for an hour or 2 to cool and firm up.
- Place the egg whites, sugar, vanilla and corn syrup in the top of a double boiler over rapidly boiling water. Beat constantly with an electric mixer on medium high until soft peaks form. It will take around 4-5 minutes.
- Transfer the mixture to a large mixing bowl or the bowl of a stand mixer.
- Beat on medium high speed, with a whisk attachment (on stand mixer) or with hand mixer for one minute.
- Let the cream cool the bowl.
Assemble the Whoopie Pies
- For the marshmallow cream: Dollop about 1 tablespoon of cream onto the center of six of the cake rounds. The cream will spread to the edge when you gently press the top cake on.For the buttercream: Pipe or dollop 1-2 tablespoons of filling onto the flat bottom of half of the cake rounds, Spread or pipe it almost to the edge. Gently press another little cake on top. ENJOY!
- These cakes will stay fresh in a sealed container for 2-3 days at room temp.