Allow butter and eggs to come to room temperature, about 30
Preheat oven to 375 degrees F.
Use a food processor to grind up Brownie Brittle™ into a fine crumb.
Pour in a microwave safe container. Place butter on top and
microwave until butter is melted, 30-45 seconds. Stir melted butter
to coat crumbs. If crumbs are still dry, add another 2 tablespoons of
Beat room temperature butter on medium speed until light and
fluffy. Scrape down the sides of the bowl. Add sugar and beat until
Add eggs, one at a time, beating each egg well. Add vanilla extract.
In a separate bowl, combine flour, graham cracker crumbs baking
powder and salt.
Slowly add half the dry ingredients, followed by half the milk and
half the sour cream. Once ingredients are mixed, add remaining dry
ingredients followed by remaining milk and sour cream. Beat on
medium speed until well combined.
Spoon about one tablespoon of Brownie Brittle into each cupcake
liner; press into the bottom of the liner. Fill liners 2/3 full with
Bake at 375 degrees F for 18-22 minutes. Remove from oven and
allow to cool completely.
For the frosting
Allow butter to come to room temperature for about 20-30
minutes, or microwave for 15 seconds straight from the
refrigerator. In your mixing bowl, whip butter on medium high
speed until light and fluffy.
Add marshmallow fluff and beat to combine.
Sift cocoa powder if necessary. Turn down the speed to low and add
cocoa powder, beating until well mixed.
Add powdered sugar, two cups at a time. Start on a low speed until
powder sugar is incorporated and increase speed as necessary. Add
milk when the frosting starts to get clumped together.
Once all the powdered sugar is mixed in, increase speed to medium
high and beat for at least 60 seconds.