For the crust

1. Assemble your 9-inch springform pan and cover the bottom and outside with plastic wrap then foil to make sure no water creeps in once the pan is in its water bath.
2. Give your graham crackers or digestive biscuits a good smash, then dump them into your food processor along with the sugar, and whiz to sandy bits.
3. With the processor still running, slowly pour in the melted butter. Mix for a few seconds until combined.
4. Dump your crumb mixture into a 9-inch springform pan and press the crumbs evenly into the bottom of the pan.

For the cheesecake

1. Preheat the oven to 325 F (160 C) and put a kettle of water on to boil.
2. In a small bowl, whisk together sour cream and heavy cream until relatively smooth. Set aside.
3. Put your cream cheese in a large mixing bowl and beat on medium low with an electric mixer for a few minutes until smooth.
4. Add the butter and continue to mix on medium low until smooth and incorporated. Next add the sugar, lemon juice, and vanilla, beating until smooth after each. Then add the eggs, one at a time, mixing well after each. Finally, blend in the cream mixture. Give the bowl a scrape, and turn your mixer on again for about 30 seconds to make sure everything is nice and smooth.
5. Pour your cheesecake mixture over your crust. Place your foil-covered pan in a roasting pan. Carefully open your oven door, pull out the rack in the middle, and place the roasting pan on it. Pour the water from your recently boiled kettle into your roasting pan until it’s about halfway up the side of the cheesecake pan. Very carefully push the rack back in and close the door.
6. Bake for about an hour and fifteen minutes or until the cheesecake is just slightly wobbly in the center.
7. Remove the whole roasting pan from the oven and allow the cheesecake to cool, still in the water, for about two hours.
8. Put some plastic wrap right on the surface of your cheesecake and refrigerate for at least 4 hours, preferably overnight.

For the topping

1. After your cheesecake is thoroughly chilled, top it with your favorite caramel sauce. Use as much as you need to make it look pretty. Sprinkle on your crunchy bits. Use as much as you like.
2. You can serve it immediately, but if you chill it again for another hour or two, your caramel won’t be as runny.