Chef's Note: Here's a fun trick--turn a pint of ice cream on its side and slice the ice cream into 1/4 - 1/2-inch rounds, keeping the cut container round on the edges to keep things clean. Transfer the round to a cookie and top with another. If it's too large, use a biscuit cutter to cut it into the right shape. Refreeze until serving.
Line a sheet pan with parchment paper2.
In the bowl of a food processor, combine the almonds paste, 1 of the egg whites 1/4 cup of the sugar, the flour, almond extract and salt. Pulse until the mixture becomes a smooth paste. Transfer to a large bowl.3.
In a metal bowl, whisk the remaining egg white until frothy. Slowly add the remaining 1/4 sugar and continue whisking until you achieve medium-stiff peaks. Stir 1/3 of the egg white mixture into the almond mixture to lighten it using a wooden spoon. Using a large rubber spatula, fold the remaining egg white mixture into the almond past mixture until will combined.4.
Using a large cookie scoop, scoop the cookie dough onto the prepared pan, spacing about 3 inches apart. Press an almond sliver onto the center of each cookie (if using). Leave the unbaked cookies, uncovered, out on your countertop an hour or 2 to form a skin. Preheat oven to 350º F. Bake for 12-15 minutes or until the edges are golden brown.5.
Serve with vanilla or chocolate ice cream.