Step 1

Preheat oven to 350°F. Assemble a 9-by-3-inch springform pan with its bottom inverted, so the raised lip faces down. Butter pan.

Step 2

In a food processor, finely grind graham crackers. Add melted butter, brown sugar, lemon zest, and 1/2 teaspoon salt; pulse until mixture resembles wet sand. Press evenly into bottom and halfway up sides of prepared pan. Bake until golden and set, 12 to 15 minutes; let cool completely.

Step 3

Reduce oven temperature to 325°. Beat cream cheese on medium speed until smooth. Gradually add granulated sugar and beat until light and fluffy, 2 to 3 minutes. Beat in lemon juice and remaining 3/4 teaspoon salt. Add eggs, one at a time, beating well after each addition. Beat in sour cream and vanilla until smooth.

Step 4

Place pan in the center of a double layer of foil. Lift edges of foil up, wrapping tightly around sides of pan and folding foil under itself as needed until flush with top of pan (this will prevent moisture from seeping in). Pour filling into pan (it should come almost to top of rim); smooth top with a small offset spatula.

Step 5

Place filled pan inside a roast- ing pan and transfer to center rack of oven. Carefully pour enough boiling water into roast- ing pan to come halfway up sides of springform pan (this is safer than pouring it in and then transferring to the oven). Bake until cake is puffed and golden brown on top and slightly wobbly in center, 1 3/4 to 2 hours (it will continue to cook as it cools).

Step 6

Carefully remove spring-form pan from roasting pan; transfer to a wire rack and let cool 20 minutes. Remove foil and run a small paring knife around sides of pan to loosen cheesecake. Let cool completely. Drape pan loosely with plastic wrap and refrigerate until cold, at least 8 hours and up to 3 days. Unmold cake and serve.