Preheat your oven to 350° F.
In two separate bowls, prepare ½ box of strawberry cake mix and ½ box of lemon cake mix according to the box instructions. For both batters combined, I used 3 eggs, 1 cup water, and ½ cup neutral oil, divided evenly between the two bowls. (My kiddos don’t like lemon, so I’m using yellow cake mix.)
Once mixed, scoop alternating tablespoons of each batter into the cupcake liners until ¾ full.
Give the pan a couple taps on the counter to set, then bake in the oven for 19–23 minutes. My oven works well with 20 minutes.
While the cupcakes are baking, make the marshmallow flowers by cutting 4 slits into 24 marshmallows, fanning the petals, and adding a yellow M&M candy (24 total) to the centers.
Once your cupcakes are done baking (a toothpick inserted into the center comes out clean), place them on a rack to cool completely before piping on the frosting.
While the cupcakes are cooling, add a 12 oz tub of prepared buttercream frosting to a large piping bag.
When the cupcakes are cool, pipe on the frosting, starting in the center of each cupcake and creating a swirl pattern to the outer edge until completely covered.
Top each cupcake with a marshmallow flower, and enjoy!
