This sugar, used in the cookies and lime ice, is great to have on hand for sprinkling on cut fruit or to add a boost to iced tea.

　　Active time: 45 min Start to finish: 45 min

Ingredients

　　6 limes

　　2 1/4 cups sugar

　　Remove zest from limes in strips with a vegetable peeler and cut away any white pith from zest (pith imparts a bitter flavor). Chop zest (about 1/2 cup), then grind in a food processor with sugar until mixture is pale green with bits of zest still visible.

　　Cooks' notes:

　　·Lime sugar may be made 3 days ahead and kept, chilled, in an airtight container.

　　·The sugar becomes aerated in the food processor; do not pack when measuring.