Lucky Marshmallow Sheet Cake
Ingredients
Scale
- 1 box vanilla cake mix. Optional: Pistachio cake mix can be used in place of vanilla if you can find it. It adds a subtle nutty flavor but isn’t required.
- Green food coloring
- 1 cup whole milk
- 1/2 cup vegetable oil
- 4 large eggs
- 1/2 cup sour cream
- 1 teaspoon vanilla extract
- 1 tablespoon cornstarch
- 1 cup salted butter, softened
- 2 cups powdered sugar
- 1 cup marshmallow fluff
- 1 teaspoon vanilla extract
- Rainbow sprinkles
- Shamrock sprinkles
- Lucky Charms marshmallows
Instructions
- Preheat the oven to 350°F. Line a 9 x 13 pan with parchment paper and lightly spray with baking spray.
- In a large bowl, combine the cake mix, milk, oil, eggs, sour cream, vanilla, cornstarch, and a few drops of green food coloring. Mix until smooth, about 30 seconds on low speed, then 1 minute on medium speed. Scrape down the sides as needed.
- Pour the batter into the prepared pan and spread evenly. Bake according to the box directions, checking a few minutes early. Let the cake cool completely.
- To make the frosting, beat the butter until pale and fluffy, about 2 minutes. Add the powdered sugar and beat until smooth. Mix in the marshmallow fluff and vanilla, then whip for one final minute until light and airy.
- Smooth the frosting evenly over the cooled cake. Sprinkle generously with rainbow and shamrock sprinkles, then arrange Lucky Charms marshmallows around the edges or scatter them over the top. Slice and serve.
Find it online: https://lifeandsprinkles.com/lucky-marshmallow-sheet-cake/