INGREDIENTS
1/4 cup
unsalted butter, softened
3/4 cup
granulated sugar
1
large egg
1 cup
all-purpose flour
1/4 cup
unsweetened cocoa powder (dark chocolate)
1/4 tsp
kosher salt
1/2 tsp
baking soda
1/2 tsp
baking powder
1/4 cup
brewed coffee (stronger the better)
1/4 cup
buttermilk
1/2 cup
unsalted butter, softened
2 cups
powdered sugar
1 tsp
vanilla extract
1 tbsp
milk
10 oz
package m&m candies