Whisk the egg whites stiff with an electric mixer in a bowl. Whisk until the whites are so stiff that you can turn the bowl upside down.
Gradually whisk the sugar into the stiff egg whites until the mixture forms peaks and becomes glossy.
Melt the chocolate over a double boiler and remove it from the heat.
If you are using whole almonds, grind them into flour in a food processor or coffee grinder. Blend until the almonds are finely ground.
Stir the melted chocolate, cold coffee, and almond flour into the meringue mixture. Stir until everything is thoroughly mixed.
Using two tablespoons, place the dough in round mounds on a baking sheet lined with parchment paper. Flatten them slightly with the spoon.
Bake the cookies at 150 degrees Celsius (302 degrees Fahrenheit) (convection) for 20-25 minutes, until the surface of the cookies is firm.
Let them cool on the parchment paper before transferring them to a wire rack.