Beat egg whites at high speed of an electric mixer until foamy.
Gradually add sugar, 1 tablespoon at a time, beating until stiff peaks form and sugar dissolves (2 to 4 minutes).
Fold in peppermint extract and chocolate morsels.
Drop egg white mixture by level tablespoonfuls, 2 inches apart, onto cookie sheets coated with cooking spray.
Bake at 200° for 2 hours or until dry.
Remove from cookie sheets, and let cookies cool completely on a wire rack.