These traditional old-world Italian "ugly but good" cookies might not win beauty contests, but their crispy, nutty perfection will win your heart with just five simple ingredients.
Roast the Nuts (Skip This Step if Yours are Roasted):
Preheat the oven to 350°F (175°C).
Spread the nuts evenly on a rimmed baking sheet and roast for 15 to 20 minutes, or until the skins darken and begin to crack.
Immediately transfer the hot nuts to a dish towel, fold the towel over them, and rub vigorously to remove the skins. A small amount of skin left on the nuts is fine; discard any skins that don't come off easily.
Transfer the skinned nuts to a food processor and pulse to achieve coarsely ground nuts, or chop them by hand using a chef's knife. Allow the nuts to cool slightly before using. The finer the grind, the less rustic the cookie, and vice versa.
Prepare the Dry Ingredients and Whip the Egg Whites:
Line the baking sheets with parchment paper.
In a mixing bowl, combine the sugar, chopped nuts, salt, and cinnamon. Stir well with a wooden spoon.
In a separate clean bowl, pour in the egg whites. Using an electric mixer, whip the egg whites until soft peaks form. If using a whisk by hand, it will require more effort but can be done.
Heat the Meringue Mixture:
Gently fold the nut and sugar mixture into the whipped egg whites until well combined.
Pour the mixture into a pot, add the vanilla, and heat over medium heat for about 5 to 8 minutes, stirring constantly, until it thickens and darkens slightly.
Form the Cookies:
To form the cookies, use two spoons or a two-tablespoon to scoop up the batter and drop it onto the prepared parchment-lined baking sheets, leaving about 2 inches of space between each. You should get about 28 cookies.
Bake the Cookies:
Reduce the oven to 300°F (150°C).
Bake each sheet one at a time for 25 to 30 minutes or until the cookies have formed firm meringues. The less you bake, the chewier they'll be, and the more you bake them, the harder they will be.
Allow the cookies to cool completely on the baking sheet before serving or storing.
Notes
NOTE: The easiest way to make these is to use egg whites (from a carton) and a kitchen scale to measure ingredients.