01 - Preheat oven to 340°F. Grease a 9-inch springform pan and line the base with parchment paper.
02 - In a medium bowl, mix crushed chocolate cookies, melted butter, sugar, and salt. 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 - In a large bowl, 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 the cooled crust, smoothing the top. Tap the pan gently to release air bubbles. Bake for 50-55 minutes, until edges are set but the center is slightly jiggly. Turn off oven, crack the door, and let cheesecake cool inside for 1 hour.
06 - Remove from oven, run a knife around the edge, and cool to room temperature. Refrigerate at least 4 hours or overnight.
07 - In a saucepan, combine cherries, sugar, lemon juice, and water. Cook over medium heat until cherries release juices (about 5 minutes). Mix cornstarch with a little cold water, stir into cherries, and simmer until thickened (2-3 minutes). Cool completely.
08 - Spread cherry topping over the chilled cheesecake before serving.