Cookies and Cream Cupcakes

INGREDIENTS

!For the cupcakes:

1/3 cup

all-purpose flour

2 tbsp

(slightly heaped) unsweetened cocoa powder

1/4 tsp

baking soda

1/4 tsp

baking powder

1/2 tsp

instant espresso powder (optional)

1/3 cup

buttermilk (or milk + 1/2 teaspoon vinegar added)

4 tsp

canola oil

1/2 tsp

vanilla extract

1/4 cup

dark brown sugar, packed

!For the frosting:

4 tbsp

unsalted butter, softened

1 cup

powdered sugar

1 tbsp

heavy cream

1/2 tsp

vanilla extract

Oreo cookies, crushed (plus extra for garnish)