1 1/4 cups chocolate or regular graham cracker crumbs (from nine 5-by 2 1/2-inch graham crackers)
3 tablespoons sugar
4 tablespoons Earth Balance vegan buttery spread, melted and cooled, plus additional for greasing pan
2 1/4 cups sugar, divided
1/3 cup water
8 ounces bittersweet chocolate (no more than 60% cacao), chopped
2 (1-pound packages silken tofu, drained
1/4 cup unsweetened cocoa powder (not Dutch-process)
2 (8-ounces) containers soy cream cheese at room temperature
1 teaspoon pure vanilla extract
Rounded 1/4 teaspoon salt
Equipment: a 9-inch springform pan