For chocolate chips, pastry chef Michelle Gayer uses any leftover chocolate pieces, in any combination: bittersweet, semi-sweet, unsweetened and white chocolate.
If using a convection oven, bake at 300 degrees for 15 minutes, rotating baking sheet halfway through baking time.
Granulated sugar can be substituted for superfine sugar, but the latter produces a more supple meringue. Superfine sugar is designed to dissolve almost instantly; you can make your own by pulsing granulated sugar in a food processor fitted with a metal blade. (makes 1 to 2 dozen)
1/2 c egg whites (from about 4 eggs)
1 c superfine sugar
2 1/2 tbsp sifted unsweetened cocoa powder
1/2 c chopped chocolate chips
Preheat oven to 350°F and line baking sheets with parchment paper.
In a double boiler over gently boiling water, combine egg whites and sugar and simmer, whisking occasionally, until sugar is dissolved. Pour mixture into bowl of an electric mixer fitted with a whisk attachment. Whip egg-white mixture on medium speed for 5 minutes, then increase to medium-high speed for 5 to 10 minutes, until mixture is stiff but not dry.
Using a rubber spatula, fold cocoa into egg-white mixture until well incorporated, then fold in chocolate chips.
Place heaping tablespoons of batter onto prepared baking sheets.
Bake 18 minutes, rotating baking sheet halfway through baking time. Remove from oven and cool cookies on baking sheets until ready to serve.
Store in a single layer in an airtight container for up to 1 day.
Courtesy of Salty Tart Bakery, Minneapolis