Make Ahead and Storage: The glazed cookies will keep airtight for up to 3 days. The glaze keeps them from going stale at first, but it begins to break down after a few days. Why It Works: A waffle iron applies direct, even high heat to the batter. The result is a cookie with all the same pros as great waffles--crisp on the outside and slightly soft inside--but just cookie-er. Pro Tip: The glaze recipe makes more than you need, but it's great to have on hand--lovely on scones, muffins, doughnuts, cupcakes, or sugar cookies. Store extra glaze in an airtight container in the refrigerator for up to 2 weeks. Bring to room temperature and stir before using again. If it dries out, thin it with water, milk, or cream.