Preheat the oven to 350°F (175°C) and line a muffin tin with cupcake liners.

In a large mixing bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt.

In another bowl, cream the softened butter until light and fluffy. Add the eggs and vanilla extract, mixing until well combined.

Gradually add the dry ingredients to the wet ingredients, alternating with the milk, and mix until just combined.

Fold in the crushed chocolate sandwich cookies.

Divide the batter evenly among the cupcake liners, filling each about ⅔ full.

Bake for 15-18 minutes, or until a toothpick inserted in the center comes out clean. Let cool completely.

In a mixing bowl, beat the softened butter until creamy.

Gradually add the powdered sugar and mix until smooth.

Add the heavy cream and vanilla extract, beating until the frosting is light and fluffy.

Fold in the crushed chocolate sandwich cookies.

Frost the cooled cupcakes with the cookies and cream frosting.

Top with additional crushed chocolate sandwich cookies if desired.