Add the cream cheese to a mixing bowl. Beat on medium with a hand mixer until the cream cheese is smooth. Scrape down the bowl.
Add the sugar and beat until incorporated. Scrape down the sides and bottom of the bowl.
Add the eggs one at a time. Beat each egg in before adding the next. Scrape down the sides and bottom of the bowl.
Add the sour cream, raspberry puree, and vanilla extract. Beat on medium until it's just incorporated. Scrape the sides and stir in any remaining sour cream or raspberry puree.
Pour half of the batter into a separate bowl. Try to keep it as even as possible. I used a scale, but a measuring cup would work as well.
Add the raspberry extract to one of the bowls of cheesecake batter. Now is the time to add food coloring if you want more of a pink color. I left it out. Stir until everything is combined.
Melt the chocolate chips in a medium bowl by microwaving for 30 seconds and stirring. Repeat until the chocolate chips are completely melted.
Add 1/2 cup of the second bowl of cheesecake batter into the bowl with the melted chocolate. Immediately start stirring in the batter into the chocolate to avoid the chocolate seizing up or cooling down too much.
Once the batter is incorporated, add the cocoa powder to the chocolate mixture. Stir until it's completely incorporated.
Scrape the chocolate mixture in with the second bowl of batter. Stir to combine.
Wrap the bottom of the springform pan with aluminum foil. Place the cheesecake into a slightly bigger pan and fill with an inch to two inches of hot water.
Add the chocolate cheesecake batter to the springform pan first. Spread it out evenly.
Slowly pour the raspberry cheesecake batter on top to avoid it plopping into the pan and disturbing the chocolate layer. Spread it out so it covers all of the chocolate batter.
Place in the oven. Let the cheesecake bake for 1 hour 20 minutes - 1 hour 30 minutes until done. To make sure the cheesecake is done, give it a wiggle. If it slightly jiggles in JUST the middle like jello, then it's done. If it jiggles on the edges, it needs to bake longer. Turn off the heat and crack the oven door slightly. Let it cool in the oven.