I’ll be the first to admit I’m not an expert on cheesecake, but I do know this; if it ain’t been baked, it ain’t a cheesecake, it’s a cream pie with a biscuit base and has no place on any menu of mine.
Cheesecake would never be my first choice; I find them a little heavy going after a good meal, but other people go gaga for them and I enjoy making them, and so for that reason this coffee and walnut number is perfectly welcome at our gaff.
I use the same basic recipe for all my cheesecakes and bake them in a water bath; I find it produces a smooth, creamy filling, almost set like a custard. I always use mascarpone instead of a cream cheese and use plain digestives for the base swapping in other ingredients if the recipe calls for it. In this case, I replace some of the biscuits with walnuts.
I’ve also incorporated a layer of chocolate over the biscuit base in this version, with the intention of providing an impermeable barrier between the liquid filling and the biscuit crumbs and I’m rather pleased with the result.
I also take the belt and braces approach of toasting the biscuit base first, doubly making sure of a crunchy base rather than a chewy one. You could of course skip both of the previous stages and take your chances.
Ingredients
(makes one 23cm cheesecake, enough for 10 – 12 portions)
For the base
200g digestives
50g walnuts
85g very soft butter
150g dark chocolate
1 x teaspoon vegetable oil (or walnut oil)
For the filling
700g mascarpone
4 x eggs + 1 extra yolk
100 ml double cream
150g caster sugar
2 x tablespoons cornflour
3 x tablespoons of coffee granules mixed with 3 tablespoons of hot water and cooled.
Preheat the oven to 180 ⁰C.
Whizz the walnuts in a food processor until you have small, even sized crumbs. Break the digestives roughly by hand into the walnuts and blitz again using the pulse setting until you have crumbs without any lumps of biscuit left. Add the butter and mix briefly to combine.
Tip the crumbs into a loose bottomed cake tin and level the surface, working the crumbs right up to the edge with the back of a spoon.
Bake the biscuit base in the oven for 10 mins to toast the crumbs. Meanwhile, melt the chocolate in a glass bowl sat over a saucepan filled with an inch of simmering water. (Ideally we want to pour the warm melted chocolate over the biscuit base whilst it’s still warm from the oven).
Once melted add the vegetable oil to the chocolate to thin it a little and stir to combine. Pour the melted chocolate over the biscuit base and spread carefully with the back of a spoon being careful not to drag up any crumbs. Refrigerate once cooled to room temperature.
Put the kettle on and turn down the oven to 170⁰C.
To make the filling, add the mascarpone, eggs, the yolk, sugar, cornflour and cream to the food processor and whizz to combine. Scrape down the sides and add the coffee. Mix again until well mixed.
Wrap the base of the cake tin in a double layer of foil to form a watertight seal, crimping the overhang. Repeat with another double layer of foil.
Place the cake tin in a deep sided roasting tin and pour the filling into the cake tin. Fill the roasting tin with recently boiled water and place the whole thing in the oven.
Check the cheesecake after an hour, mine usually takes 1h 15mins until there is no wobble left in the centre, however the cheesecake will puff up slightly on account of the eggs and will wobble because of it, but the centre shouldn’t ripple.
Turn the oven off and leave the cheesecake in there for 10 minutes with the door ajar. Remove from the oven, lift the cheesecake from the roasting tin, remove the foil and leave to cool in the tin on a wire rack. Refrigerate once the cheesecake is sufficiently cool.