This looks a little like a Mille Feuille because it has several thin layers. If you wish you can replace the vanilla extract with coffee extract. This a recipe my grand mother used to make and she would be overjoyed to see it on this website —MarieGlobetrotter
In a bowl, whisk the butter and the sugar together to obtain a smooth mixture. It must be smooth enough to spread it on the cake later on.
In separate bowl, combine the milk and the vanilla extract
Make the Millefeuille on a rectangular plate. For the first bottom layer : Soak 1 Petit Beurre in milk (not too long or it will break). Do the same with three other Petits Beurres to make this bottom layer.
Careful spread some of the butter mixture on top of the layer. You don’t need to put a lot. Repeat these steps until you have no more Petit Beurre left (5 layers).
Spread the remaining butter on top and on the sides of the cake. Top everything, including the sides, with chocolate sprinkles.
Cover the cake and put it in the freezer for at least two hours. Enjoy!