Source: How to make a baked cheesecake
- 60 g digestive biscuits
- 60 g ginger nuts
- 50 g butter
- 600 g cream cheese
- 4 tbsp cornflour
- 150 g caster sugar
- 200 g sour cream
- 0.5 lemon zested
- 1 tsp vanilla extract
- 5 eggs large, at room temperature, plus 1 egg white
Heat the oven to 200C/390F/gas 6 and put a baking tray on the middle shelf to heat up (putting the cake base on a heated sheet will help it crisp up). Lightly grease a 20cm springform cake tin with oil or butter.
Put the biscuits in a resealable bag, seal and bash with a rolling pin to yield a mix of crumbs and slightly larger lumps – you can use a food processor, if you like, but take care not to break down the biscuits too much. (Use just digestives, ginger nuts or other biscuits entirely if you prefer, but I think this combination gives the perfect texture and flavour.)
Melt the butter in a small pan or in the microwave. Put the biscuit crumbs into a bowl and pour in the butter, plus a pinch of salt, and mix well to combine. Spoon into the greased tin, spread out and use the bottom of a glass to press it down to make a firm, compact base, going slightly up the sides, if necessary.
Put the tin on the tray in the hot oven and bake for 10 minutes. Meanwhile, prepare the topping. Drain off any excess liquid from the cheese, if need be, then put it in a large bowl and beat with a wooden spoon to loosen, before whisking to get rid of any lumps.
Put the cornflour and sugar in a medium bowl, then whisk in the sour cream a bit at a time, until well combined. Mix into the cream cheese, along with the vanilla extract and lemon zest. (Play with the flavourings: orange or lime zest are also nice, particularly with chocolate biscuits, or use orange flower water or a pinch of nutmeg instead of the vanilla.)
Beat the whole eggs in a bowl – keep back the white for later – then gradually whisk into the cheese mixture, making sure each addition is incorporated before adding the next. Beat until creamy and smooth without any lumps. Taste (provided you don’t mind raw eggs) and add more zest, vanilla or sugar, if you like.
Put the egg white in a bowl and whisk briefly to loosen. Take the tin out of the oven, leaving the baking sheet in there, and turn down the temperature to 130C/260F/gas ½. Brush the egg white over the base, being very gentle so as not to disturb the crumb, then leave to sit while the oven cools.
Pour the cheese mixture into the tin and shake gently to help level it out. Skim a finger across the top to get rid of any air bubbles, then return the tin to the oven for about 90 minutes, until the filling is set, but still slightly wobbly in the middle. Once it’s done, turn off the oven and take out the tin.
Run a small palette or butter knife around the edge of the cake, then put it back in the oven and leave to cool completely before releasing the cheesecake from its tin: this should stop the top cracking. If it does so regardless, a dollop of fruit compote or an artfully placed handful of fresh berries will hide a multitude of sins.