Lucky Charms Cupcakes with Marshmallow Buttercream Frosting

Introduction

Turn your favorite childhood cereal into a magical dessert. These cupcakes pack the nostalgic flavor of toasted oat cereal into a tender crumb, crowned with a fluffy, marshmallow-rich frosting. You get a sweet surprise of colorful marshmallow bits in every bite.

This recipe and accompanying image were created with the help of AI for inspiration and guidance. Results may vary depending on ingredients, equipment, and technique.

Prep & Cook Time

Prep Time: 25 minutes

Cook Time: 18 minutes

Total Time: 43 minutes

Servings: 16 cupcakes

Ingredients

1½ cups all purpose flour
1 cup Lucky Charms cereal ((marshmallows picked out), ground)
1 cup granulated sugar
1¾ teaspoons baking powder
⅔ teaspoon salt
3 large eggs (room temperature)
1 cup whole milk
½ cup vegetable oil
1⅓ teaspoons vanilla extract
1½ cups salted butter (room temperature)
3 cups powdered sugar (sifted)
¾ cup heavy cream
1 teaspoon vanilla extract
2 cups marshmallow fluff
¼ teaspoon green food coloring (optional)

Instructions

Preheat your oven to 350°F (175°C) and line two muffin tins with 16 paper liners.
In a large bowl, whisk together the flour, ground Lucky Charms cereal, granulated sugar, baking powder, and salt.
In a separate medium bowl, whisk the eggs, milk, vegetable oil, and the 1⅓ teaspoons of vanilla extract until smooth.
Divide the batter evenly among the prepared liners, filling each about two-thirds full.
Bake for 16-18 minutes, or until a toothpick inserted into the center of a cupcake comes out clean. Let cool in the tins for 5 minutes, then transfer to a wire rack to cool completely before frosting.
For the frosting: In the bowl of a stand mixer fitted with the paddle attachment, beat the softened butter on medium-high speed for 3-4 minutes until very light and fluffy.
With the mixer on low, gradually add the sifted powdered sugar until incorporated. Scrape down the bowl.
Add the heavy cream and the 1 teaspoon of vanilla extract. Beat on medium-high speed for another 3 minutes, until very smooth and creamy.
Add the marshmallow fluff and optional green food coloring. Beat on medium speed until fully combined and fluffy, about 2 minutes.
Frost the completely cooled cupcakes using a piping bag or an offset spatula. Garnish with extra Lucky Charms cereal marshmallows if desired.

Variations

Cereal Milk Frosting: Steep the toasted oat cereal pieces in the heavy cream for 30 minutes, then strain, and use the infused cream in the frosting.
Stuffed Cupcakes: Use a cupcake corer to remove the center of each cooled cupcake and fill it with a spoonful of marshmallow fluff before frosting.
Ice Cream Topping: Crumble a cupcake over a bowl of vanilla ice cream for a fun sundae.
Mini Treats: Bake the batter in mini muffin tins for bite-sized treats, adjusting the bake time to about 10-12 minutes.

Tips for Success

Ensure your butter and eggs are truly at room temperature for a smooth batter and the fluffiest frosting.
When grinding the cereal (without the marshmallows), pulse just a few times to create a coarse flour; over-processing can make it gummy.
Don’t skip sifting the powdered sugar for the frosting to avoid any lumps.
For the best piping consistency, chill the frosting for 15 minutes if your kitchen is very warm.

Storage & Reheating

FAQ

Can I use unsalted butter?

Yes, but add ¼ teaspoon of salt to the frosting recipe if you do.

What does grinding the cereal do?

It incorporates the distinct toasted oat flavor of Lucky Charms throughout the cupcake batter, giving it a unique taste and slight texture.

My frosting seems too soft. How can I fix it?

The frosting can soften if the butter was too warm. Simply chill the entire bowl of frosting in the refrigerator for 20-30 minutes, then re-whip it until it holds a stiff peak.

Can I use the whole cereal, including the marshmallows?

It’s not recommended for the cupcake batter, as the colored marshmallows can melt and streak the batter. Save them for garnish.

Why is my cupcake dense?

This is likely from overmixing the batter after adding the wet ingredients. Mix just until the ingredients are combined.

Can I make these ahead of time?

Yes, you can bake the cupcakes a day in advance. Store them unfrosted in an airtight container and make the frosting the day you plan to serve them.