Birthday Cake Slice Marshmallows

These puffy marshmallows look just like slices of birthday cake! They’ll make a fun addition to your party treats, or package them for take-home favors.

My love for making homemade marshmallows begin back in 2013 when I first figured out how to make marshmallow ropes. It was such a fun project. The ropes were so tactile and flexible, and when they were wound into a ball they looked like a skein of puffy yarn. It was hard to believe they were edible, but they were so tasty! That kitchen adventure opened up a whole new world of ideas, and marshmallow became a new art medium for me.

I’ve had the idea for these cake slice marshmallows for a long time, but it took me a while to sit down and figure out the logistics. In the end it was simpler than I expected, and equally as fun as the marshmallow ropes!

The ‘yellow cake’ marshmallow layers are flavored with LorAnn Cake Batter Flavor, and the ‘pink frosting’ marshmallow has a small dose of Wilton Butter Flavor. Together the flavors are a fun play on classic birthday cake with buttercream frosting.

Make the Layers

The two yellow layers are made with a big batch of marshmallow poured into a 13×9-inch pan. After it firms, cut two rounds from the sheet using a 5-inch pastry cutter. You’ll have marshmallow left over, so just chop them up and save them for an awesome hot cocoa topping.

You’ll need a 6×3-inch round cake pan, well greased with cooking spray. Line it with a sheet of parchment paper that extends at least 3-inches over the top edge of the pan.

Mold the Marshmallow

Now that the pan is ready to hand, the pink marshmallow can be whipped together. When the marshmallow mixture is ready, pour it into the pan to 2-inches deep. Press a yellow layer into the pink marshmallow until the yellow and pink layers are even at the surface. Top with more pink marshmallow and repeat with the second yellow layer. Finally, fill the parchment to the top. You’re aiming for a 6-inch tall end result (lower LH picture).

Let the marshmallow stand uncovered in the pan overnight. The next day you can pull the marshmallow out of the pan by the parchment paper and dust it with powdered coating. At this stage, the candy looks like one giant marshmallow that could make one heck of a s’more!

When it comes time to slice the marshmallow, use a large sharp chef’s knife that has been warmed under a stream of hot water and wiped dry. This makes for a clean cut. It’s crazy how the marshmallow started swaying to and fro immediately after I carved it in two. It may look like the cake was cut unevenly, but the pieces are just doing a marshmallow wobble.

I piped a small shell border of buttercream around the top and bottom edges of the slices. It’s just enough to hold on a few colorful sprinkles and give the cake a birthday party vibe. The sprinkles I used are from Sweetapolita, custom made for Lyndsay’s book release last year, but you can find a similar option here!

A piece of this marshmallow cake is quite large, with each slice equal to about 5 marshmallows.  That’s kind of a lot to eat in one sitting, so I think they’d be really cute all packaged up for take-away favors.

This was a fun idea to explore, and I may end up experimenting with other flavors. I’m already itching to try red velvet and chocolate versions!

Birthday Cake Slice Marshmallows

Heather Baird

These puffy marshmallows look just like slices of birthday cake! They’ll make a fun addition to your party treats, or package them for take-home favors.

5 from 2 votes

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Prep Time 45 minutes mins

Overnight to 24 hour resting time 1 day d

Total Time 1 day d 45 minutes mins

Course Dessert

Cuisine American

Servings 8

Equipment

• 6×3 inch cake pan
• parchment paper

Ingredients

 

US CustomaryMetric

 

1x2x3x

Yellow cake marshmallow layers

• 4 packets .25 oz. each powdered unflavored gelatin
• 1 cup 240 ml cold water
• 1 1/2 cups 300g granulated sugar
• 1 cup 240 ml light corn syrup
• 1/2 cup 120 ml water
• 1/4 teaspoon fine grain salt

Golden yellow gel food color

• 1/2 teaspoon LorAnn concentrated cake batter flavor
• Coating
• 1/2 cup corn starch
• 1/2 cup powdered sugar

Pink frosting marshmallow

• 4 packets .25 oz. each powdered unflavored gelatin
• 1 cup 240 ml cold water
• 1 1/2 cups 300g granulated sugar
• 1 cup 240 ml light corn syrup
• 1/2 cup 120 ml water
• 1/4 teaspoon fine grain salt
• Neon pink gel food color
• 1 teaspoon Wilton butter flavor

Décors

• 1/2 cup buttercream frosting or royal icing, see footnote
• 3-4 tablespoons colorful sprinkles
• Spray a 9×13-inch cake pan with cooking spray.

Instructions

 

• Yellow cake marshmallow layers: Whisk together the gelatin and cold water in a small bowl. Let set until gelatin absorbs liquid.
• In a saucepan with a candy thermometer inserted, combine sugar, 1/2 cup corn syrup, 1/2 cup water and salt. Place over high heat and bring to a boil. Meanwhile, pour the remaining 1/2 cup corn syrup in the bowl of a standing mixer fitted with the whisk attachment. Heat the gelatin in the microwave or on the stove-top until melted completely and pour into the mixing bowl with the corn syrup. Turn mixer on low and keep it stirring until the sugar syrup is ready.
• When the syrup reaches 240°F, slowly pour it into the mixer bowl. Increase the speed to medium and beat for 5 minutes, then increase to medium-high and beat 5 more minutes. Finally, increase to highest speed and beat 1-2 more minutes, add cake batter flavor then beat again for 1-2 minutes. Mixture should be opaque and tripled in volume. Add yellow food coloring and beat until incorporated.
• Pour the marshmallow into the prepared pan and let stand until set, about 2 hours.
• Coating: Stir together the corn starch and powdered sugar in a bowl. Sift about 1/4 cup over a work surface.
• Turn out the marshmallow onto the coating. Sift a little more powder over the surface of the marshmallow and cut out two 5-inch circles using a pastry ring. Cut leftover marshmallow into pieces, coat with powder, and save for snacking. Let the two yellow rounds stand uncovered while you make the pink marshmallow.
• Grease a 6×3 inch round cake pan with cooking spray. Line the edges with parchment paper so that the paper extends 3 inches over the top edge of the pan (for a total height of 6-inches in the pan – see blog photo with ruler).
• For the pink marshmallow, repeat the instructions for the yellow marshmallow exactly, except use 1 teaspoon butter flavor in place of the cake batter flavor, and use neon pink food color in place of the yellow.
• Pour some of the pink marshmallow into the prepared pan, about 2-inches up the side. Press a yellow layer into the pink marshmallow until the yellow and pink layers are even. Top with more pink marshmallow and add another yellow layer. Finally, fill the parchment to the top with pink marshmallow.
• Let the marshmallow stand uncovered in the pan overnight. When set, pull the marshmallow out of the pan by the parchment paper and dust it with the coating.
• Cut the marshmallow into pieces using a sharp chef’s knife that has been warmed under hot water and wiped dry. Cut the marshmallow cake into four pieces, and then each piece into 2, giving a total yield of 8 pieces.
• Decors: Lay each piece on its side on serving plates and pipe a buttercream border on the top and bottom edges of the slices. Cover with sprinkles and let stand until set.

Notes

If packaging these for favors, use royal icing that crusts to hard candy consistency for the buttercream borders.

Keyword fun food, gelatin, homemade marshmallow

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