01 -
Turn your oven to 400°F (200°C). Using parchment paper, trace your 9x13-inch pan onto it and lay it on a big baking tray. Put butter, salt, and water in a saucepan, then heat until boiling and butter melts. Add all the flour at once, stirring quickly to form a dough ball. Let it cool for 5 minutes. Beat in one egg at a time, making sure each egg is well mixed before adding the next. Spread 1¼ cups of dough on the parchment-covered tray, leaving a ½-inch edge clear. Put the rest of the dough directly into the dry 9x13-inch pan. Bake for 15-25 minutes or until the pieces are golden. Let them cool completely.
02 -
Stir the milk into the French vanilla pudding mix, then pop it in the fridge for 5 minutes to set up. Whisk heavy cream, powdered sugar, and vanilla together on high speed until stiff peaks form. Gently fold the pudding into the whipped cream, cover, and refrigerate.
03 -
Using a bowl, whip butter, a pinch of salt, and vanilla extract until creamy. Slowly mix in powdered sugar and cocoa powder—switching off with splashes of milk—until smooth and fluffy. Keep it aside.
04 -
Take the pastry base from the 9x13 pan and evenly spread the prepared cream filling over it. Cut the second pastry layer to size and carefully place it over the filling. Spread the chocolate frosting over the top layer evenly.
05 -
Refrigerate the assembled cake for 6 hours or overnight so it sets properly. Slice it into squares before serving.