Sweet 16 Cupcakes (Easy Pull-Apart Number Cake)
If you're looking for a fun birthday dessert that's guaranteed to get people talking, these Sweet 16 cupcakes are just the thing.
I recently made these for my granddaughter's sixteenth birthday, and they couldn't have turned out better. Starting with a doctored strawberry cake mix, I topped each cupcake with fluffy marshmallow buttercream in three shades of pink, added a few white chocolate flowers and sprinkles, then arranged everything into the number 16.
To finish the display, I piped the word "Sweet" in melted almond bark, sprinkled it with pink sanding sugar, and placed it beside the cupcakes. It was a simple little touch that tied the whole theme together.
The birthday girl was absolutely tickled when she saw them!
Best of all, the cupcakes were every bit as delicious as they were pretty. We ended up sending the leftovers home with family members and even shared some with the restaurant staff. The hostess couldn't stop talking about the marshmallow buttercream—and especially the little white chocolate flower on top!
If you're planning a birthday celebration, be sure to check out my Themed Birthday Parties for Girls, Ultimate Birthday Party Guide, and my collection of Birthday Cake Ideas for even more inspiration. (Link these throughout the post.)
Why I Didn't Make a Traditional Pull-Apart Cake
Some people would call this a pull-apart cupcake cake, but I actually chose a different approach.
Traditional pull-apart cakes are beautiful, but they usually require spreading frosting between all of the cupcakes to hide the gaps. Once guests start pulling cupcakes apart, that frosting can end up everywhere—on hands, clothes, plates, and tables.
Since we were celebrating at a restaurant, I wanted something a little neater.
Instead of frosting all of the cupcakes together, I decorated each one individually, just as I would if I were serving them separately. Then I simply arranged them into the shape of the number 16.
The finished display has the same wow factor, but each guest can simply pick up a cupcake without disturbing the rest of the design.
Honestly, I think I'll make them this way from now on.
Ingredients
You will find a printable recipe card at the bottom of this post but here's a glance at what you're going to need to make these cupcakes. You can choose any flavor you like, but most 16-year-olds love strawberry, which is why I went that direction.
For the Strawberry Cupcakes
- 1 box strawberry cake mix
- 4 large eggs
- ½ cup vegetable oil
- 1 cup milk
- 2 tablespoons Sonic Strawberry Instant Pudding Mix (optional, but recommended)
- ½ cup rainbow sprinkles, folded in just before baking
For the Marshmallow Buttercream
- 1 cup (2 sticks) unsalted butter, softened
- 1 cup shortening
- 1 (7-ounce) jar marshmallow fluff
- 4–5 cups powdered sugar
- 1 teaspoon strawberry extract
- Heavy cream (or milk), as needed to reach piping consistency
- Pink gel food coloring (for three shades of pink)
Decorations
- White chocolate (almond bark) flowers
- Pink sprinkles
- Pink sanding sugar
- Additional melted almond bark (to pipe the word "Sweet," optional)
The result was moist, flavorful cupcakes with beautifully domed tops that were sturdy enough to hold generous swirls of frosting.
How to Make Sweet 16 Cupcakes
These are so much fun to make. Here's how you're going to do it:
Preheat oven to 350 degrees Fahrenheit.
Combine cake mix, milk, eggs, and oil in the bowl of a stand mixer (or regular mixing bowl). Mix well.
Gently fold in sprinkles, stirring only until incorporated. (Over-mixing will cause the colors to bleed.)
Use an ice cream scoop to fill liners of the cupcake tin.
Place in oven and bake for 16 minutes or until the cupcakes spring back to the touch.
Remove from oven and allow to cool while you make the frosting.
Choosing the Arrangement
Before the cupcakes were even frosted I laid them out to see how many it would take to create the number 16.
Make the Frosting
This is my traditional marshmallow fluff with a bit more powdered sugar than usual to help it hold its shape.
Beat butter until light and creamy. Add shortening and continue to beat.
Add powdered sugar and mix slowly until it comes together. Add marshmallow fluff and extract and mix until you get the consistency you like. It has to be pipe-able, so keep that in mind. You can thin with cream or milk if it's too thick. You can add more powdered sugar if it's too loose.
The Easy Ombre Frosting Trick
One of my favorite parts of this project was how easy the frosting turned out to be.
I only made one batch of marshmallow buttercream. After mixing it, I added just a drop or two of pink gel food coloring to create the lightest shade and set it aside in a separate bowl.
Then I added another drop or two to the frosting remaining in the mixing bowl to make the medium pink, which was placed in its own bowl.
Finally, I added more coloring to the remaining frosting until I reached the darkest shade.
- Three beautiful colors.
- One batch of frosting.
- No guesswork.
The same technique works with virtually any gel food coloring, so you can create ombre cupcakes for baby showers, weddings, graduations, Valentine's Day, Christmas, Easter, or any birthday theme you can imagine.
Decorating Tips
I used several different piping tips instead of the same one over and over.
Mixing different swirls and textures makes the finished cupcakes look much more elaborate than they actually are.
Once everything was piped, I added a few sprinkles to the centers and tucked white chocolate flowers here and there across the display.
Those little details only took a few extra minutes, but they really elevated the finished presentation.
My Experience
One of the things I love most about baking is creating desserts that look like they came from a bakery without requiring professional decorating skills or complicated recipes. Over the years I've developed dozens of doctored cake mix recipes because I know how much busy home bakers appreciate shortcuts that don't sacrifice flavor.
This Sweet 16 cupcake display is a perfect example. It starts with a simple boxed cake mix, uses one batch of frosting in three shades, and comes together with a handful of piping tips and a little creativity.
Frosting these cupcakes is, no doubt, the best part of all. Rosettes. Swirls. Puffs. Ruffles. All of it came straight from my imagination and no two cupcakes were the same. And here's the cool part: yours will look different from mine, depending on the tips you choose and the colors of your buttercream.
Piping really is an artist endeavor and I'm here for it every time!
The result of my labors? A lovely and unique dessert that made my granddaughter feel incredibly special on one of the biggest birthdays of her life.
Seeing her smile when she walked in—and hearing guests rave about both the cupcakes and the frosting—made every minute in the kitchen worthwhile.
Frequently Asked Questions
One doctored cake mix made 21 cupcakes, which was just enough to create my number 16 display with one cupcake left over.
Absolutely. Vanilla, white, chocolate, lemon, funfetti, red velvet, or strawberry all work beautifully.
Yes! Simply tint one batch of frosting from light to dark using gel food coloring. You can match any party theme or school colors.
If you've made some of my other recipes, you know I often flavor buttercream with fruit preserves. I considered adding strawberry preserves to this frosting, but decided against it for one important reason: I wanted those beautiful soft shades of pink. I knew that adding preserves would make the colors harder to achieve.
I transported the decorated cupcakes in a cupcake carrier. Once I arrived at the restaurant, I arranged them on the serving board in the shape of the number 16.
To keep them from sliding around, I placed a small piece of removable double-sided mounting tape beneath each cupcake liner. It worked perfectly and kept everything securely in place throughout the party.
Yes. If you're serving them at home, you can assemble the display the day before.
If you're traveling, I recommend transporting the cupcakes separately and arranging them at your destination.
Not at all. I actually prefer this method because every cupcake stays beautiful, guests can grab one easily, and there isn't frosting smeared between every cupcake.
I think it's just as pretty—and much easier to serve.
More Birthday Desserts You'll Love
If you're planning a birthday celebration, don't miss these reader favorites:
- Themed Birthday Parties for Girls
- Ultimate Birthday Party Guide
- Birthday Cake Recipes
- Marshmallow Buttercream Frosting
- How to Doctor a Boxed Cake Mix
- White Chocolate Flowers Tutorial
- Easy Cupcake Decorating Ideas
- Cake Mix Cupcakes
Thanks for Stopping By!
If you make this Sweet 16 cupcake cake, please leave a comment. We love hearing from our readers. Before you go, why not pin some photos to your Pinterest boards?
Janice Thompson is a professional baker, cake designer, and author with over 20 years of experience creating unique cakes and desserts. She’s the creator of Out of the Box Baking, where she shares her favorite doctored cake mix recipes, tutorials, and baking tips. Learn more →
Sweet 16 Cupcakes
These beautiful Sweet 16 cupcakes start with a doctored strawberry cake mix and are topped with fluffy strawberry marshmallow buttercream in three shades of pink. Arrange them into the number 16 for a simple but unforgettable birthday centerpiece.
Ingredients
- Strawberry Cupcakes
- 1 box strawberry cake mix
- 4 large eggs
- ½ cup vegetable oil
- 1 cup milk
- 2 tablespoons Sonic Strawberry Instant Pudding Mix (optional)
- ½ cup rainbow sprinkles
- Strawberry Marshmallow Buttercream
- 1 cup butter, softened
- 1 cup shortening
- 1 (7-ounce) jar marshmallow fluff
- 4–5 cups powdered sugar
- 1 teaspoon strawberry extract
- Heavy cream or milk, as needed
- Decorations
- Pink gel food coloring
- White chocolate flowers (optional)
- Pink sprinkles
- Pink sanding sugar
- Melted almond bark for piping the word "Sweet" (optional)
Instructions
Make the Cupcakes
Preheat oven to 350 degrees.
Line cupcake pans with paper liners.
In a large mixing bowl combine cake mix, eggs, oil, milk, and strawberry pudding mix.
Beat until smooth, about 2 minutes.
Fold rainbow sprinkles into the batter.
Fill cupcake liners about two-thirds full.
Bake for 18-22 minutes, or until a toothpick comes out clean.
Cool completely before frosting.
Make the Frosting
Beat butter and shortening until light and fluffy.
Add marshmallow fluff and beat well.
Mix in strawberry extract.
Gradually add powdered sugar.
Add heavy cream, one tablespoon at a time, until the frosting reaches a smooth piping consistency.
Create the Ombre Colors
Leave all frosting in one bowl.
Tint with one or two drops of pink gel coloring to make the lightest shade.
Fill one piping bag.
Add additional coloring to the remaining frosting for a medium pink.
Fill a second piping bag.
Add more coloring until you reach a dark pink.
Fill the third piping bag.
Decorate
Pipe assorted swirls using several decorating tips.
Alternate frosting colors around the cupcakes.
Add sprinkles and white chocolate flowers.
Arrange cupcakes into the number 16 on a serving board.
If desired, secure each cupcake liner with a small piece of removable double-sided mounting tape.
Pipe the word "Sweet" using melted almond bark and sprinkle with pink sanding sugar.
Notes
One batch makes 20 cupcakes, perfect for creating the number 16.
The Sonic strawberry pudding mix adds extra strawberry flavor but is optional.
Strawberry extract flavors the frosting without changing the soft pink ombre colors.
For best results, transport cupcakes in a cupcake carrier and assemble the display at your destination.
Using several piping tips creates a bakery-style look with very little extra effort.
The frosting can be tinted to match any party theme or holiday.
