The Cream Slice, or in French “Mille-feuille (thousand-leaf), vanilla slice, cream slice, custard slice, also known as the Napoleon, is a pastry originating in France.
Traditionally, a cream slice is made up of three layers of puff pastry (pâte feuilletée), alternating with two layers of pastry cream (crème pâtissière), but sometimes whipped cream, or jam. The top is usually glazed with icing or fondant in alternating white (icing) and brown (chocolate) strips, and combed. Alternatively the top pastry layer may be dusted with confectioner's sugar, cocoa, or pulverized nuts (e.g. roasted almonds).