Be sure the nectarines are ripe but only slightly soft. To ripen them, leave them on the counter for a few days. Or, to speed the process, place them in a paper bag with an apple. Leave the bag on the counter for a day or two.

CRUST
1 1/2 cups all-purpose flour
1 tablespoon sugar
1/4 teaspoon salt
1/2 cup unsalted butter, chilled, cut up
4 to 6 tablespoons cold water

FILLING
8 cups sliced (generous 1/2 inch) unpeeled nectarines (about 3 1/2 lb.)
3/4 cup packed light brown sugar
3 tablespoons all-purpose flour
2 teaspoons grated lemon peel
1 teaspoon grated nutmeg
1 teaspoon lemon juice
1 teaspoon vanilla extract
2 tablespoons sugar
1/2 teaspoon ground cinnamon