With gooey tops and fudgy centers, these bakery-style Marshmallow Brownies melt in your mouth with every bite. Featuring rich, cocoa powder brownies swirled with fluffy marshmallow creme, this quick and delicious treat takes only 15 minutes to prep.
Preheat oven to 350 degrees. Grease an 8 x 8 metal baking pan then line with parchment paper. Set aside.
In a large bowl, whisk together butter and sugar until combined.
Add vanilla and eggs. Whisk vigorously until smooth and glossy.
In a separate bowl, sift together cocoa powder, flour and salt.
Add dry ingredients to wet then stir with a spoon until just combined. Note: Batter will be thick.
Spoon brownie batter into baking pan then smooth and level the top with a spatula.
Place marshmallow creme in a small heat-safe bowl then microwave for 5 - 10 seconds or until creme softens enough to swirl. Avoid melting the marshmallow creme.
Using a spoon, drop large dollops of marshmallow creme onto brownie batter in random placements.
With the tip of a knife, gently swirl marshmallow creme into brownie batter.
Bake for 20 - 25 minutes or until a tester inserted into the center comes out with a few moist crumbs. Do not overbake or brownies will be dry.
Place brownie pan on a baking rack to cool to room temperature, approximately 1 hour, before slicing.
Store brownies in an airtight container at room temperature up to 3 days.