How to Make It
Preheat the oven to 350° and line 2 baking sheets with parchment paper. Spread the hazelnuts in a pie plate and toast for 14 minutes, until the skins blister. Transfer the nuts to a kitchen towel and rub together to remove the skins. Coarsely chop and transfer to a bowl. Add the cocoa, cornstarch, nibs, chocolate and cardamom. Lower the oven to 300°.
In a medium bowl, using an electric mixer, beat the egg whites with the cream of tartar and salt until soft peaks form. Add the sugar in a thin stream and beat until the whites are stiff and glossy. Beat in the vanilla. Fold in the dry ingredients, leaving some streaks.
Scoop 8 level tablespoon-size mounds of the meringue onto each baking sheet. Scoop the remaining meringue directly on top of the existing mounds, as if forming little snowmen.
Bake the cookies in the upper and lower thirds of the oven for about 30 minutes, until firm when tapped; shift the sheets halfway through baking. Transfer the sheets to racks and let the cookies cool before serving.