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

In a bowl, combine all-purpose flour, baking powder, baking soda, and salt. Whisk until well mixed.

In a large bowl, cream together granulated sugar and softened butter until light and fluffy, about 3-5 minutes.

Add eggs one at a time, mixing well after each. Stir in milk and vanilla extract.

Gradually add the flour mixture to the wet ingredients, mixing gently until just combined.

Fill cupcake liners about two-thirds full with batter. Bake for 18-20 minutes or until a toothpick comes out clean.

Allow the cupcakes to cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.

Beat together softened butter and cookie butter for frosting until creamy. Gradually add powdered sugar and a splash of milk until desired consistency.

Once cool, frost each cupcake with the cookie butter frosting and garnish with crushed Biscoff cookies.