Preheat the oven to 350 degrees F. Begin making the graham cracker crust. Combine graham crackers, sugar, cinnamon, and a pinch of salt in a food processor. Then pour in melted butter and pulse until smooth and texture resembles wet sand.
Line a 9 inch springform pan with parchment paper along the bottom and sides. and add graham cracker crumbs. Press the crumbs into the bottom of the pan and against the sides of the pan until a crust forms. Bake in the oven for 12 minutes. until golden brown and set. Set aside to cool. Reduce oven temperature to 325 degrees F.
Bring 6 cups of water to a boil.
Now make the cheesecake filling. Add room temperature cream cheese and sugar to the bowl of a stand mixer fitted with the paddle attachment. Beat cream cheese on low speed until smooth, about 1-2 minutes. Then add the vanilla extract. Begin adding eggs and egg yolk, one at a time, allowing each egg to become fully incorporated prior to adding the next. Scrape down the sides of the bowl with a rubber spatula and continue to mix to ensure cheesecake mixture is smooth.
In a small bowl, whisk together sour cream, heavy cream, kosher salt, and cornstarch. Whisk together until just combined and smooth and add to the bowl of the stand mixer. Mix until just combined, about 20 seconds. Scrape down the sides of the bowl again and mix for another 20 seconds.
Pour cheesecake filling into the cooled graham cracker crust. Tap the cheesecake against the counter to pop any air bubbles.
Pour boiling water into a 9x13 pan. Place the cheesecake into the oven on the middle rack and carefully and swiftly place the pan of hot water on the bottom rack of the oven. Quickly close the oven door to make sure to trap in the steam. Bake cheesecake for 1 hour and 15 minutes.
While the cheesecake is baking, make the pastry cream topping. Add milk to a medium saucepan over low heat. Allow the milk mixture to simmer for 5-7 minutes, until just warmed all the way through (about 105 degrees F).
In a large bowl, combine egg yolks, cornstarch, and sugar. Whisk together for 2-3 minutes, until a thick paste forms. Slowly begin to add the milk mixture, about a ½ cup at a time, whisking constantly to prevent the eggs from cooking.
Once all of the milk is added, pour everything back into the saucepan. Increase the heat to medium, and bring to a boil, whisking constantly. Once the cream is boiling and begins to thicken, remove from the heat and whisk vigorously for 1 minute. Then add a pinch of salt, vanilla bean paste, and butter. Whisk until the butter is fully melted. (if the cream seems clumpy, press the mixture through a fine mesh sieve so that it's nice and smooth.)
Allow the cream to cool to room temperature, about 45 minutes to 1 hour (this aligns with the time that the cheesecake will be cooled in the oven, see next step). Give it a good whisk (or use a hand mixer to ensure that the cream is nice and smooth).
Once the cheesecake is finished baking, the cheesecake should be slightly jiggly - like jello. Turn off the oven and crack the oven door. Let the cheesecake sit for one hour. Then remove from the oven and carefully add the pastry cream on top. Place into the refrigerator to set for 4 hours, ideally overnight.
Before serving, sprinkle 3 tablespoons of sugar on top of the pastry cream. Use a torch to brulee the sugar until slightly blackened and caramelized. Let it cool for 1-2 minutes, then add the remaining 3 tbsp of sugar and torch again. Top with raspberries or fresh berries of choice, optional.
Notes
Room Temperature Ingredients Are Key: Ensure your cream cheese, eggs, and sour cream are all at room temperature. This helps create a silky cheesecake batter without lumps.
Mix the cheesecake batter on low speed! It's tempting to want to whip it up on high, but low and slow is key here. Whipping the cheesecake too quickly can add to much air and cause the cheesecake to crack while cooling.
Don’t Skip the Water Bath: Baking your cheesecake in a water bath prevents cracks by providing a gentle, even heat. Wrap the sides of the springform pan tightly in foil to keep water from seeping in.
Cool Gradually: Cheesecakes are delicate. Let it cool in the oven with the door cracked for about an hour before transferring it to the fridge. This prevents sudden temperature changes that can cause cracks.
Crispy Caramelized Sugar: Sprinkle an even thin layer of sugar on top of the cheesecake before torching. Move the torch in a circular motion to caramelize evenly, avoiding burnt spots.
Avoid using a hand mixer: the lowest settings on the hand mixer are still a bit fast and may incorporate too much air into the cheesecake. I recommend using a stand mixer if you have one!