Adjust the oven rack to the lower-middle position. And preheat the oven to 350°F (180°C,) or 160°C for a fan oven.
Lightly grease a 9-inch (23 cm) springform pan with butter, then line it with parchment paper (bottom and sides).
Make the graham cracker crust by crushing up the graham crackers in a food processor, then in a bowl combine crumbs with melted butter and sugar. Stir and let the butter moisten the crumbs.
Press the mixture onto the bottom of the pan, and make it flat. I like to use a measuring cup or a glass to help flatten and press the crust.
Bake in the oven for 8 minutes then remove from the oven and allow to cool completely.
Lower the temperature of the oven to 325F°/160°C. (275°F/140°C fan oven)
Wrap two large pieces of foil around the outside of the springform pan to protect it, taking care to cover the seams.
In a bowl of a stand mixer fitted with a paddle attachment, beat the cream cheese and sugar on high speed until creamy. Then add the eggs one by one mixing in between until just incorporated. Add sour cream, heavy cream, and vanilla and mix until smooth but make sure not overmix the batter (if you overmix, the cheesecake will crack as it bakes).
Pour the mixture onto the prepared graham cracker crust.
Prepare a water bath. Choose a roasting pan that fits in the 9-inch springform pan. Place the roasting pan in the oven, then place the cheesecake pan in the middle of it. Carefully pour boiling water into the space around the cheesecake until the water level is 1 inch deep.
Bake for 55-60 minutes. If the cheesecake starts to brown too much at the top, just tent it with foil to protect it from browning. It’s done when the edges are completely set but the center is still jiggly. Switch off the oven.
Slightly open the oven door, and allow the cheesecake to cool down in the oven for 1 hour. Then remove from the oven and let it cool down uncovered until it’s completely cooled. Chill in the fridge for at least 6 hours or overnight before serving.
To serve, loosen up the edges of the cheesecake from the pan with a knife, and then remove from pan and slice with a knife (run it under warm water and dry it, this will help you get neat slices). If you like, serve topped with homemade strawberry sauce.