MAKES ABOUT 70 COOKIES
4½ oz egg whites (from about 3 large eggs) ½ tsp cream of tartar 1 cup + 3 tbsp granulated sugar ¾ tsp cornstarch ⅛ tsp baking powder ½ tsp pure vanilla extract Dark Chocolate Coating 3½ oz dark chocolate, chopped 1½ oz milk chocolate, chopped 1⅓ cups hazelnuts, toasted and
very finely chopped White Chocolate Coating 5 oz white chocolate, chopped ½ cup finely chopped dried strawberries Preheat the oven to 275°F. Place the egg whites in the bowl of an electric mixer fitted with the whisk attachment. Beat on medium-high speed until they appear foamy, about 2 minutes. Add the cream of tartar and continue to beat until the egg whites are stiff but not dry or crumbly, about 30 seconds. Place the sugar in a bowl, add the cornstarch and baking powder, and gradually add the mixture to the egg whites 1 tablespoon at a time. Continue to beat until the egg white mixture is thick and glossy, about 3 minutes. Beat in the vanilla extract. Spoon mixture into a piping bag with a ⅔" tip in place.
Line two large baking sheets with parchment paper, sticking each piece to the baking sheet with a dab of meringue under the corners. Pipe small drops onto each sheet; the base of each drop should be about 1" wide. Raise the piping bag as you pipe so the drops are about 2" high with a fine tip at the top. Once all the meringues have been piped, place both baking sheets in the oven at once. Immediately lower the oven temperature to 250°F (you want it to be slightly hotter when they go in to give the meringues a crunch) and bake for 2½ hours. The meringues are done when they look dry and sound hollow when tapped gently underneath. Turn off the oven; prop open the door and leave the meringues inside until cool.
To make the dark chocolate coating, place the dark and milk chocolates in a medium heatproof bowl over a pan of simmering water, making sure the base of the bowl is not touching the water. Stir occasionally, until the chocolate is melted. Place the hazelnuts in a small bowl. Dip the base of each meringue into the chocolate, then into the hazelnuts; place meringues on a parchment paper-lined baking sheet to set.
To make the white chocolate coating, follow the instructions for the dark chocolate coating, dipping the base of each meringue into the strawberries instead of the hazelnuts.