Orange and lemon mousse cake

The search for the perfect cheesecake -- or rather, the one that perfectly matches my favourite cheesecake ever -- continues. I quite like the fudgy, mouth-coating "New York" versions; but not as much as I like ones with light, mousse-like toppings.

This one is not quite it, being too creamy. But it is good in its own right. I got it from the BBC Good Food website (here). My version has less biscuit, because I used a 20 cm cake tin; less fromage frais, because 400 ml was all I had; and lemon zest in place of the berries, because it is not summer.

150 g digestive biscuits
75 g butter
4 leaves gelatine
142 ml single cream
400 g fromage frais
100 g caster sugar
Zest of 1 lemon and 1 orange
4 tbsp orange juice
284 ml double cream

Place the base of a 20 cm, springform cake tin on to a sheet of greaseproof paper, draw round it in pencil, and cut out the shape. Smear some butter on to the base. Stick the paper on top.

Whizz the biscuits in a food processor; or put them in a plastic bag, tie it up, and bash them with a rolling pin. Melt the butter over a gentle heat in a saucepan. Tip in the biscuit crumbs, and mix. Spread the crumbs over the cake tin base, compacting them with the back of a spoon. Crumbs will fall off the side. Do the best you can to get a level layer of compacted crumbs to the edge of the base. Put the base into the freezer.

Soak the gelatine leaves in cold water. Meanwhile, heat the single cream gently in a saucepan. After four or five minutes, the gelatine will be soft and slithery; squeeze out the moisture. When the cream is bubbling, take it off the heat. Stir in the gelatine leaves, one by one. Unlike powdered gelatine, they dissolve very easily. Allow to cool.

Beat together the fromage frais, sugar, orange and lemon zest, and orange juice. Stir in the gelatine mixture. Whip the double cream until it forms peaks, but stop before it stiffens.

The recipe tells you to "fold" the double cream into the fruity mixture. But you have to stir it in quite thoroughly, or the cream will remain in blobs.

Attach the biscuit base to the rest of the cake tin. Pour in the mousse mixture, cover with clingfilm, and chill. It needs at least three hours. You might want to make the cake the day before eating it.

To serve, run a knife between the mousse and the tin, and release the spring.