Preheat the oven to 250°. Line a baking sheet with parchment paper. In a small bowl, whisk the confectioners' sugar with the cocoa powder and coffee.
In a medium bowl, beat the egg whites at high speed until frothy. Add 1 tablespoon of the granulated sugar and beat for 30 seconds; gradually beat in the remaining 3 tablespoons of sugar until the meringue is thick and glossy, about 2 minutes longer. Fold in the cocoa mixture in two batches.
Mound scant tablespoons of the meringue 1 inch apart on the prepared baking sheet and top each one with an espresso bean. Bake the meringues for 1 hour, or until set and dry. Let the meringues cool completely on the sheet before serving.
One Meringue Calories 24 kcal, Total Fat 0.1 gm, Saturated Fat 0.1 gm, Protein 1 gm, Carbohydrates 6 gm.