01 - Preheat oven to 340°F. Grease a 9-inch springform pan and line the base with parchment paper.
02 - Mix crushed chocolate cookies, melted butter, sugar, and salt in a medium bowl. Press firmly into the bottom of the pan. Bake for 10 minutes, then let cool.
03 - Melt dark chocolate in a heatproof bowl over simmering water (double boiler); let cool slightly.
04 - Beat cream cheese and sugar until smooth. Add eggs one at a time, mixing well after each. Mix in sour cream, vanilla, flour, and salt until just combined. Fold in melted chocolate.
05 - Pour filling over cooled crust, smoothing the top. Tap pan gently to release air bubbles. Bake for 50-55 minutes until edges are set but center is slightly jiggly.
06 - Turn off oven, crack door, and let cheesecake cool inside for 1 hour. Remove, run knife around edge, and cool to room temperature.
07 - Refrigerate at least 4 hours or overnight until completely set.
08 - Combine cherries, sugar, lemon juice, and water in saucepan. Cook over medium heat until cherries release juices (5 minutes). Mix cornstarch with cold water, stir in, and simmer until thickened (2-3 minutes). Cool completely.
09 - Spread cherry topping over chilled cheesecake before serving.