Summer fruit has a window, and the window closes fast. These cookies are built around the fruits of June and July at their peak — blueberries, cherries, peaches, apricots, strawberries and rhubarb — and the practices that made them last: jam, pie filling, preserves, things put up in jars against the coming cold. Every flavor in this collection comes from the idea that the best of the season is worth the work of keeping it.