1. Preheat oven to 325°F (163°C). Line a 9-inch (23cm) springform pan with parchment paper in the bottom and grease the sides.
2. Combine the crust ingredients in a small bowl. Press the mixture into the bottom and up the sides of the springform pan.
3. Bake the crust for 10 minutes, then set aside to cool.
4. Cover the outsides of the pan with aluminum foil so that water from the water bath cannot get in (see how I prepare my pan for a water bath). Set prepared pan aside.

CHEESECAKE FILLING

5. Reduce oven temperature to 300°F (148°C).
6. In a large bowl, beat the cream cheese, brown sugar and flour on low speed until well combined and smooth. Be sure to use low speed to reduce the amount of air added to the batter, which can cause cracks. Scrape down the sides of the bowl.
7. Add the sour cream and vanilla extract and mix on low speed until well combined.
8. Add the eggs one at a time, mixing slowly to combine after each addition. Scrape down the sides of the bowl as needed to make sure everything is well combined.
9. Pour the cheesecake batter into the crust.
10. Place the springform pan inside another larger pan. Fill the outside pan with enough warm water to go about halfway up the sides of the springform pan. The water should not go above the top edge of the aluminum foil on the springform pan.
11. Bake for 1 hour 30 minutes. The center should be set, but still jiggly.
12. Turn off the oven and leave the door closed for 30 minutes. The cheesecake will continue to cook, but slowly begin to cool as well.
13. Crack the door of the oven for 30 minutes to allow the cheesecake to continue to cool slowly. This process helps prevent cracking. At this point, go ahead and make the pastry cream.

PASTRY CREAM

14. To make the pastry cream, put the egg yolks in a medium sized bowl and gently beat them together. Set aside.
15. Add the sugar, cornstarch and milk to a large saucepan and mix until smooth.
16. Cook, stirring continuously, over medium heat until mixture just begins to thicken and simmer. Be careful not to boil it.
17. Next, temper the eggs by slowly adding about 1/4 cup hot milk mixture to the egg yolks, whisking quickly and constantly until combined. This process of slowly warming the egg yolks prevents them from becoming scrambled/chunky.
18. Add the tempered egg mixture back into the rest of the hot milk mixture. Place the pan back on the heat and bring to a light boil. Allow to boil for 1 minute, stirring continuously. Don’t boil for too long, or you can overcook it and it’ll actually break down, rather than get thicker.
19. Remove from heat and add butter and vanilla extract. Stir until melted and smooth.
20. When the cheesecake comes out of the oven, spread the pastry cream evenly on top of the cheesecake and cover with clear wrap that’s touching the top of the cream.
21. Remove the cheesecake from the water bath wrapping and refrigerate until firm, 5-6 hours or overnight.

TO FINISH IT OFF

22. When you’re ready to serve the cheesecake, remove it from the springform pan and place on a serving dish.
23. Sprinkle the additional sugar over the top of the cheesecake and use a butane kitchen torch to cook/caramelize it.