Recipe: In the pink

THIS IS a lovely summery take on the classic Italian dessert tiramisu. Rhubarb is fantastic for its tart flavour and vibrant colour, but you can adapt the recipe depending on the time of year: red plums work well when the rhubarb season is fading out. The key factor is to use a slightly tart fruit to contrast with the sweet, creamy custard.

At the Cook School, we always make this pud in a martini glass, partly because it looks pretty, but also because is works well for the proportions, allowing a nice, thick topping of cream and a smaller tart fruitiness underneath. It also provides a good surface area for plenty of amoretti biscuit sprinkles, which give a tasty contrasting crunch to the texture.

A chef's tip for cooking rhubarb is to add a splash of grenadine, the red, syrupy cocktail ingredient. It keeps the colour really vibrant and doesn't detract from that distinctive rhubarb flavour. However, if you do this don't add too much extra sugar or the final taste will be overly sweet.

Rhubarb tiramisu

Serves four

300g rhubarb
1 tbsp caster sugar
3 tbsp water
½ tsp ginger root, shredded
dash grenadine (if you don't use grenadine, up the sugar by 1 tbsp)

For the creamy filling

3 egg yolks
85g caster sugar
1 vanilla pod
250g mascarpone cheese
150ml double cream
25ml Grand Marnier
amoretti biscuits, lightly crushed

For the rhubarb crisps

½ thick stick of rhubarb
icing sugar, to coat

First make the rhubarb crisps. Very thinly slice the rhubarb at a 45-degree angle and cut into lengths of about 4cm. Lay the thin slices (about 1mm each) on to non-stick baking paper or bako-glide. Using a small sieve, liberally sprinkle the slices with icing sugar and pop the tray into an 80°C oven (or at its lowest setting). After about an hour turn the slices over and return to the oven for 20 minutes or so. The exact drying time will depend on your oven and how thinly the rhubarb has been cut. The slices will not go completely crisp until cold.

When you think they are ready, take one from the oven and leave it to cool. If it becomes glassy in appearance, remove the others from the oven as well. The crisps can be made up to a couple of days in advance but must be stored in an airtight box to avoid becoming soft and leathery.

For the rhubarb and ginger tiramisu base, cut the 300g of rhubarb into 4cm lengths and set aside. Take a pan where the rhubarb will be not more than 3cm deep and add the caster sugar, water and shredded ginger and heat until the sugar has dissolved. Add the rhubarb and cook gently until it is soft but still has a firmer core. Quickly remove from the heat and transfer into a cold bowl to cool.

For the cream filling, place a metal whisking bowl over a pan of just simmering water. Add the egg yolks and caster sugar and whisk until they become thick and foamy. The mixture will become pale and roughly double in volume. Take care not to overheat the mixture or it will turn to scrambled eggs – 77°C on a thermoprobe is perfect. The mixture should be quite thick. Set aside to cool, but do not refrigerate.

In a separate bowl, add the vanilla seeds to the mascarpone and gently mix and soften using the back of a fork. In a third bowl, gently whisk the double cream until just beginning to leave a light ribbon on the surface. Don't over-mix.

When the egg mix has completely cooled, it will have thickened. Fold in the Grand Marnier to loosen. Fold the egg mixture into the mascarpone and thoroughly mix. Finally, very gently fold in the double cream to the mix. Do not over-mix as this may curdle.

To assemble the desserts, take a Martini-style cocktail glass and place a heaped tablespoon of gingered rhubarb in the bottom of the glass, keeping back some of the juices. Half fill the remaining space with the mascarpone mix and sprinkle some of the crushed Amoretti biscuits over the top. Spoon some of the juices over the biscuits then fill the rest of the glass with cream. Wait for the cream to settle otherwise it may spread out and spill over the edges. Place in the fridge for two hours to set. Repeat this with the remaining glasses.

To serve, sprinkle more of the crushed biscuits over the top and decorate with the rhubarb crisps. Don't do this until the last minute, or the biscuits and crisps will start to soften.

Critical points

Egg yolks and sugar mixed over simmering water with alcohol added is known as sabayon in France and zabaglione in Italy. The trick is to get the temperature of the water right. Start with it simmering, not cold, or you'll be there all day. Also, don't let it boil fast; you're after a consistent gentle simmer. And lastly, keep whisking until it thickens then remove from the heat. A thermoprobe reading of 77°C takes away the guesswork.

Always mix the egg mixture into the mascarpone rather than the other way round to prevent any solidified eggy bits stuck to the side of the bowl spoiling the smooth texture of the mix.

For this recipe, it's essential not to over-whip the cream. Do it in a cold bowl with cold cream and get it just to the ribbon stage. There should be no stiffness whatsoever. Take great care when you fold this cream into the mascarpone and egg as the whole thing can curdle at this point.

The rhubarb crisps are very simple to create and make the pud look extra special – they taste pretty good too. The best method for slicing evenly is to use a mandoline, but a very sharp knife and careful hand is fine. They should be roughly 1mm thick per slice. Don't have your oven too hot, and test one for crispness before removing them all from the oven. They'll crisp up after cooling down, so wait with your test piece to see if this happens.