In a large mixing bowl, use a fork to toss the graham cracker crumbs, sugar, and cinnamon together. Add the melted butter, mixing until all crumbs are moistened. Press mixture into the bottom and up the sides of a 9-inch springform pan. Refrigerate while you work on the filling.

Preheat the oven to 500ºF. In the bowl of a stand mixer fitted with the paddle attachment, beat cream cheese on high until creamy, about 2-3 minutes. Add the sugar and continue beating for another 2-3 minutes. Scrape down the sides of the bowl, add the cornstarch, vanilla, lemon juice, and salt, and beat until incorporated, 1-3 minutes. Beat in the eggs, two at a time, until combined. Try not to overmix.

Pour filling into the crust, smoothing out the top. Bake cheesecake for 10 minutes. Then without opening the oven door, reduce the temperature to 200ºF, and continue to bake for 80-85 minutes, or until center appears nearly set when shaken.

Transfer the cheesecake to a wire rack and run a knife around the edges. Allow to cool for at least 2 hours before covering cheesecake and chilling in the refrigerator for at least 8 hours.

In a small bowl, stir together the cornstarch and 2 Tablespoons of water. In a saucepan, heat 2 cups of the berries, both sugars, the water, lemon juice, and salt over medium-high heat until it begins to boil. Allow to boil and stir constantly for 3-4 minutes, or until juices have released and berries begin to break up. Add the remaining cup of berries, along with the cornstarch-water mixture and continue stirring over low heat until mixture thickens. Remove from heat immediately and pour into a bowl to cool.*

To serve, remove sides of the springform pan and slice with a sharp knife, wiping the knife clean between slices. Serve with blackberry topping.