The ultimate 'posh' rhubarb and custard? How to make rhubarb, raspberry and thyme mille-feuille

Spring is the time for delicately flavoured forced rhubarb. In the main recipe, simple rhubarb and custard flavours are elevated to something rather grown up.

Recipe: Rhubarb, raspberry and thyme mille-feuille

Ingredients

Serves 6

• 2 organic eggs
• 2tbspn custard powder
• 1tbspn caster sugar
• 500ml whole milk
• 300ml double cream
• 1½ sheets pre-rolled puff pastry
• 400g rhubarb
• 6 sprigs thyme
• 20g unsalted butter
• 1tbspn caster sugar
• 200g icing sugar
• 200g raspberries
• Fresh thyme sprigs

Method

This is a cheat’s method of making crème diplomat, which involves starting with a crème pâtissière. First, whisk the eggs into the custard powder and sugar in a large bowl. Bring the milk to the stage just before boiling and pour it over the custard mixture, whisking continuously.

Pour everything back into the saucepan and, over a low heat, bring it to a boil while stirring – it should thicken. Transfer to a bowl, cover with cling-film to prevent a skin forming and chill for an hour in your refrigerator. Whip the double cream until thick and set aside.

Preheat your oven to 220˚C/430˚F/gas mark 7. Cut the puff-pastry sheets into halves so you have three even-sized rectangles and arrange them on top of greaseproof paper on a baking sheet.

Cover the pastry with a second sheet of greaseproof paper and a second baking sheet – this will stop the pastry puffing up.

Bake for 18–20 minutes until light brown. Trim the pastry slices while warm with a sharp knife so that they are perfectly matched and set aside.

Trim the ends of the rhubarb, cut it into even lengths and arrange on a large sheet of foil. Add the thyme and butter and sprinkle over the caster sugar. Seal and bake in the oven for 12–15 minutes (this can be done at the same time as the puff pastry) – it should be soft, but not mushy. Open the foil pouch and leave to cool. Select your best piece of puff pastry for the top and place it on a wire rack. Mix the icing sugar with a splash of water into a thick but pourable paste. Spread evenly over the pastry top using a palette knife and set aside.

To assemble, whisk together the custard and whipped cream to make the crème diplomat and transfer to a piping bag with a simple nozzle. Put a sheet of puff pastry on a serving plate and top with a third of the rhubarb, then a third of the raspberries.

Pipe into the gaps between the fruit and along the edges. Repeat with a second layer of puff pastry. Top with the final layer of iced pastry and decorate with rhubarb, raspberries, piped crème diplomat and fresh thyme sprigs. Serve immediately (although it will hold in a cool room for a few hours).

More ways with rhubarb

Rose-water rhubarb with roasted nectarines and pistachios

On a baking sheet, arrange trimmed stems of rhubarb and a halved nectarine per person. Whisk together orange juice, honey and a drop or two of rose water (taste for strength, but less is more). Drizzle over the fruit and bake in a moderately hot oven for 12 minutes, until cooked, but not mushy. Put a dollop of Greek yoghurt onto each plate and top with the rhubarb, nectarine and pan juices. Sprinkle with chopped pistachios and serve.

Rhubarb-and-ginger upside-down cake

Grease an 8in cake tin and line the base with greaseproof paper. Arrange 200g of trimmed rhubarb in the base and sprinkle with 2tbspn of caster sugar. In a large mixing bowl, combine 175g of unsalted butter with 175g of caster sugar. Beat in 3 eggs, a little vanilla-bean paste and then 175g of self-raising flour. Fold in 100g of chopped preserved-ginger pieces and a little syrup from the jar. Pour the mixture over the rhubarb and bake in a moderately hot oven for about 40 minutes or until a skewer comes out clean. Turn out onto a plate and, while hot, brush with ginger syrup from the jar. Serve with a dollop of whipped cream.

Rhubarb-and-ginger gin and tonics

Put 1kg of trimmed rhubarb in a large preserving jar with 400g of caster sugar and leave overnight. The next day, add 190g of stem ginger in syrup and 800ml of gin. Seal and leave for at least two weeks before serving with tonic.