If you’re a fan of lemonade, give limeade—made with limes instead of lemons—a try!
Cut 2 limes in half lengthwise through both ends. Lay limes halves, flat side down, on cutting board, then cut each half crosswise into thin semicircles; discard ends. Put half of lime slices in large pitcher and set aside. Put remaining lime slices in large bowl and add sugar.
Use potato masher to mash sugar and lime slices together until sugar is completely wet, about 1 minute. Set aside.
Cut remaining 10 limes in half crosswise. Use citrus juicer to squeeze juice into liquid measuring cup. You should have a little over 1 cup. (Save any extra juice for another use.)
Pour lime juice and water into bowl with lime slices and sugar. Use rubber spatula to stir mixture until sugar is completely dissolved, about 1 minute.
Set fine-mesh strainer over pitcher. Carefully pour mixture through strainer. Use rubber spatula to press on limes to get out as much juice as possible. Discard lime slices in strainer.
Mashing sliced limes with granulated sugar extracts oils contained in the peel and punches up the lime flavor. Try to purchase large limes that give to gentle pressure; hard limes have thicker skin and yield less juice.