Why it Works: The Way the Cookie Crumbles
Cookies taste great the day they are made; maintaining their taste and texture for another day is often a challenge. Sometimes after storing, crisp cookies become soft and chewy, and chewy cookies get hard. The culprit behind this texture change is water. Many ingredients in your kitchen love to absorb water. Even when baked into a cookie, these ingredients continue to absorb water from the air or from other cookies. There are ways around this. Store completely cooled cookies in an airtight container (if warm, condensation builds and is reabsorbed by the cookie) and separate soft and crisp cookies (the water from the chewy cookies will move to the crisp, drying the soft cookies and softening the crisp ones). In this recipe you are filling a crisp cookie with a wet filling. No matter how hard you try, some of that water will move from the filling to the cookie. So plan on serving them as soon as possible after filling.