Preheat the oven to 350 degrees F (175 degrees C). Grease a 9-inch springform pan with cooking spray and set aside.
In a medium bowl, combine the crushed animal cracker crumbs, 3/4 cup sugar, and 1 tablespoon instant coffee granules. Pour in the 1/4 cup melted butter and stir until the crumbs are evenly moistened. Press the mixture firmly into the bottom of the prepared springform pan to form an even crust. Set aside.
In the bowl of an electric mixer, whisk together 1 1/2 cups sugar, the 1/3 cup cocoa powder, 2 teaspoons instant coffee, and 3 tablespoons cornstarch until blended. Add the softened cream cheese and beat on medium speed until fully incorporated and no lumps remain.
Beat in the eggs one at a time, mixing just until combined after each addition. Stir in 1 teaspoon vanilla extract with the last egg. Gently fold in 1/2 cup chopped pecans with a spatula. Pour the filling into the prepared crust and smooth the top.
Bake in the preheated oven at 350°F for 15 minutes. Then reduce the oven temperature to 200 degrees F (95 degrees C) and continue baking for 2 hours. After baking, turn off the oven and let the cheesecake remain inside for an additional 2 hours to cool slowly.
Remove the cheesecake from the oven and let it cool to room temperature on a wire rack. Once cooled, melt 1/2 cup semisweet chocolate chips with 2 tablespoons milk in a small saucepan over low heat, stirring frequently until smooth and glossy.
Remove the sides of the springform pan, spread 1/2 cup marshmallow creme evenly over the cheesecake top, then spoon or drizzle the melted chocolate over the marshmallow layer. Sprinkle 1/4 cup chopped pecans evenly over the chocolate. Chill the cheesecake completely in the refrigerator (at least 3 hours or overnight) before slicing and serving.
Notes
Use room-temperature cream cheese and eggs for a smoother filling. Don’t overmix the filling once the eggs are added to prevent cracks.