Whip butter and sugar until smooth and fluffy.
Beat in the eggs.
Add the dries and milk and beat until fluffy.
Fold in crushed cookies by hand.
Divide batter evenly into three lined 6" pans.
Bake until golden brown.
Make Biscoff frosting by whipping butters then adding in the powdered sugar and milk until light and fluffy.
Attach bottom cake layer to your serving plate.
Top with a layer of frosting.
Drizzle with Biscoff spread, then repeat layers again to finally top it all off with the final cake layer.
Coat with a final layer of Biscoff buttercream and streak with extra Biscoff spead if you like. Slice, serve and enjoy!