Preheat oven to 325°F (165°C).

In a bowl, mix graham cracker crumbs with melted butter and press into the bottom of a 9-inch springform pan.

In a large mixing bowl, beat cream cheese and sugar until smooth.

Add eggs one at a time, beating well after each addition.

Stir in vanilla extract, cocoa powder, buttermilk, and food coloring until smooth.

Fold in sour cream and heavy cream until just combined.

Pour the batter over the crust in the springform pan.

Bake for 50-55 minutes or until the center is set and the top looks dry.

Let cool in the pan for 10 minutes, then transfer to a wire rack to cool completely. Refrigerate for at least 4 hours before serving.