Preheat the oven to 400 degrees.
Place the puff pastry on a lightly floured work surface. Sprinkle the pastry with a little flour and roll out to form a 12inch square. Brush away any excess flour and trim the edges to make a perfect square.
Cut the puff pastry into nine 3 1/2inch squares. Transfer them to a parchment-lined baking sheet.
In a small bowl, whisk together the egg yolk and heavy cream. Neatly brush a little of the egg wash along 2 of the edges of each square. Place the chocolate, divided equally, and 1/4 teaspoon of the almonds on each square. Fold down the unwashed edges to enclose the chocolate, forming a triangle. Using your fingers, gently but firmly press the puff pastry edges together to seal them.
Place the baking sheet in the freezer for 20 minutes, or until the pastry is thoroughly chilled. Remove from the freezer and brush the tops of the turnovers with the remaining egg wash.
Place in the oven and bake until the turnovers are puffed and golden, about 15 minutes.
c.1997, M.S. Milliken & S. Feniger, all rights reserved