Sift in the cornstarch and add a pinch of salt. Mix for a few more minutes, then pour everything into the saucepan with the milk.

Increase the heat to medium-low and cook, stirring, until the mixture thickens. Remove from heat and let it cool, stirring occasionally to help it cool faster. Add the hazelnuts, roughly chopped and toasted in a skillet beforehand. Transfer to a bowl and cover with plastic wrap pressed directly onto the surface. Refrigerate for at least 40 minutes.

Once the cream is chilled, remove from the fridge, discard the plastic wrap, and stir. Prepare two large glasses and spoon the pastry cream into them, pressing down to fill the bottom. Sift unsweetened cocoa powder on top using a fine mesh strainer and finish with whole almonds.