3/4 cup (1 1/2 sticks) unsalted butter, melted (divided use)
2 1/2 cups graham-cracker crumbs
2 3/4 cups sugar (divided use)
1 teaspoon plus a pinch salt (divided use)
2 pounds cream cheese, room temperature
1/4 cup sour cream
1 (15-ounce) can pure pumpkin
6 large eggs, room temperature, lightly beaten
1 tablespoon vanilla extract
2 1/2 teaspoons ground cinnamon
1 teaspoon ground ginger
1/4 teaspoon ground cloves
2 cups sweetened whipped cream or whipped topping
1/3 cup toasted pecans, roughly chopped
Position a rack in the center of the oven and preheat to 325 degrees.
Brush a 10-inch springform pan with some of the butter. Stir remaining butter into crumbs with 1/4 cup sugar and pinch salt. Press mixture into bottom and up sides of pan, packing it tightly and evenly. Bake until golden brown, 15 to 20 minutes.
Cool on a rack, then wrap outside of springform pan with foil and place in a roasting pan.
Bring a medium pot of water to a boil. Meanwhile, beat cream cheese with a mixer until smooth. Add remaining 2 1/2 cups sugar and beat until just light, scraping down sides of bowl and beaters as needed. Beat in the sour cream, then add pumpkin, eggs, vanilla, 1 teaspoon salt, cinnamon, ginger and cloves and beat until just combined. Pour into cooled crust.
Without pulling rack out, gently place roasting pan in oven and pour boiling water into roasting pan until it comes about halfway up side of springform pan. Bake until outside of cheesecake sets but center is still loose, about 1 hour 45 minutes. Turn off oven and open door briefly to let out some heat. Leave cheesecake in oven for 1 more hour, then carefully remove from roasting pan and cool on a rack. Run a knife around edges of springform pan, cover and refrigerate at least 8 hours or overnight.
Bring cheesecake to room temperature 30 minutes before serving. Unlock and remove springform ring. To finish, place a dollop of whipped cream on each slice and sprinkle with toasted pecans.