Beat egg whites (at room temperature) in a medium mixing bowl until foamy; add sugar, 2 tablespoons at a time, beating until stiff peaks form. Fold in vanilla and pecans.

Drop mixture by heaping teaspoonfuls 2 inches apart onto waxed paper-lined cookies sheets. Bake at 250 degrees for 55 minutes. Remove from waxed paper and cool on wire racks. Store immediately in airtight containers.