In a heavy-bottom saucepan melt the chocolate on low heat. Stir continuously with a whisk.
When the chocolate has completely melted, take it off the heat immediately to avoid burning.
Leave it aside to completely cool off before adding it to the cream cheese mixture.
In a large bowl, combine cream cheese with cacao powder, and both sugars. Use a whisk to make sure everything is mixed in smoothly.
Add in the eggs and mix well.
Mix in the vanilla extract.
In a separate bowl, whisk the heavy cream to soft peaks. I recommend using an electric mixer at medium speed.
Add the melted chocolate to the cheesecake batter and mix it in until smooth consistency. DO NOT ADD THE MELTED CHOCOLATE IF STILL WARM.
Gently fold in the whipped heavy cream. It's important to use a folding technique rather than a mixing technique. This way you don't lose that airy texture of the whipped cream.
Pour 3/4 of the cheesecake filling into the spring form pan.
Take the blackberries and pitted cherries and slice them in halves and quarters.
Arrange them on top of the batter in a single uniform layer. Don't push them in or throw them in from a height. This will make them sink to the bottom and we don't want that.
Pour the remaining 1/4 of the cheesecake batter on top of the fruits, making sure to cover them completely.
Pour about 1 inch of hot water into an oven dish while your oven is preheating. Close the door and wait for a few minutes to create steam.
Add the cheesecake to the oven and quickly close the door to not let the steam come out.
Bake chocolate cherry cheesecake at 325°F (160°C) for about 1 hour and 10 minutes or until the cake is set (but the center is still a bit jiggly).
Remove the cheesecake from the oven and place the springform on a wire rack to allow air to circulate and cool it off completely.
Run the tip of a knife around the sides of the pan to prevent ruptures and cracking in the cake.
Place the cheesecake in the fridge for at least 6 hours (or overnight) to set.