01 -
Turn your oven to 350°F. Get a 9-inch square baking pan, line it with parchment paper, and give it a coat of baking spray.
02 -
Follow the brownie box instructions to prepare the mix. Pour the batter into your lined pan and spread it in a flat, even layer. Drop marshmallow cream in dollops on top and swirl with a knife. Don’t worry if it looks messy—it bakes beautifully!
03 -
Bake per brownie box directions. Once done, let it cool completely. Want extra fudgy brownies? Pop them in the fridge for an hour or two after they've cooled.
04 -
In a big bowl, use your electric mixer on medium to beat the softened butter for 2 minutes. Keep going until it's creamy and smooth.
05 -
Add the marshmallow fluff into the butter and mix until you’ve got an even mixture.
06 -
While mixing on low, add the powdered sugar, one cup at a time. Slowly increase speed to medium-high. Stop to scrape the bowl whenever needed. Toss in the vanilla and food coloring, then beat until the color is completely blended.
07 -
If the frosting feels too thick, mix in heavy cream one tablespoon at a time until it’s as spreadable as you like. Afterward, beat on high for a minute or so to fluff it up.
08 -
Spread as much frosting as you’d like over your cooled brownies. If there’s extra, save it for other treats. Top with edible gold flakes and Lucky Charms marshmallows.
09 -
Cut the brownies into squares and dig in!