FOR THE CRUST
1 1/4 cups graham-cracker crumbs (from 10 whole crackers)
1/4 cup sugar
4 tablespoons unsalted butter, melted
FOR THE FILLING
4 packages (8 ounces each) bar cream cheese, very soft
1 1/4 cups sugar
3 tablespoons all-purpose flour
1 cup canned pumpkin puree
2 tablespoons pumpkin-pie spice
1 tablespoon vanilla extract
1/2 teaspoon salt
4 large eggs, room temperature
Preheat oven to 350 degrees, with rack in center. Assemble a 9-inch nonstick springform pan, with the raised side of the bottom part facing up.
Make the crust: In a medium bowl, mix cracker crumbs, sugar, and butter until moistened; press firmly into bottom of pan. Bake until golden around edges, 10 to 12 minutes.
Make the filling: With an electric mixer, beat cream cheese and sugar on low speed until smooth; mix in flour (do not overmix). Add pumpkin puree, pie spice, vanilla, and salt; mix just until smooth. Add eggs one at a time, mixing until each is incorporated before adding the next.
Place springform pan on a rimmed baking sheet. Pour filling into springform, and gently smooth top. Transfer to oven; reduce oven heat to 300 degrees. Bake 45 minutes. Turn off oven; let cheesecake stay in oven 2 hours more (without opening).
Remove from oven; cool completely. Cover with plastic wrap; refrigerate until firm, at least 4 hours. Unmold before serving.