Rhubarb excites mixed emotions. Ambrose Bierce, dyspeptic satirist and author of The Devil’s Dictionary, described it as “the vegetable essence of stomach ache”. John Thorne, the pen behind the cult culinary newsletter Simple Cooking, is clearly a fan, fantasizing about those two ideal mates, rhubarb and strawberries, “whose tastes and textures meld into a sort of subtle transcendental oneness”.
You may – like Bierce – despise this curious vegetable (into which botanical category it more accurately falls). Or perhaps you share Thorne’s fondness for it and are currently celebrating its reappearance in markets, shops and gardens after the seemingly endless winter. Either way you can hardly miss it if you live in the northern hemisphere, for its moment is now.
Broadly speaking, rhubarb falls into two categories. Firstly, there is the so-called ‘forced’ kind, which appears in late winter and early spring. It is cultivated in warm sheds in total darkness and in some places still traditionally picked by candlelight. Because the plant is never exposed to light, photosynthesis does not occur, the stalks take on a brilliant, lipstick-pink color and the (inedible) leaves a rather anemic yellow. Rhubarb treated in this way is also the tenderest and tastiest. Some of the most celebrated is grown in the Rhubarb Triangle in west Yorkshire, England, which in 2010 received PDO (Protected Designation of Origin) status under the name Yorkshire Forced Rhubarb.
The second is field rhubarb, which appears from late spring through summer, depending on the local climate. Since this kind is grown outdoors in full daylight, the stalks are pale green in color and tinged with only a suspicion of pink, the texture is noticeably coarser and the foliage deep green.
You can use either sort for this delicious, meringue-topped tart, which has its roots in Alsace; but it’s undeniably prettier if you use forced rhubarb. If using field rhubarb, you may need to peel away the outer, fibrous layer before chopping it in pieces.
To avoid the risk of a soggy bottom to your tart (ever-present with rhubarb because of its high water content), dredge the fruit with sugar and leave it in a bowl for several hours, or better still overnight. This way it will render much of its juice. The baking then falls into three steps: first, bake the sugared fruit ‘dry’ in its pastry case, then mix some of the juice with cornstarch, egg and cream, pour it over the fruit and bake again. Finally, daub it with the meringue and return the tart to the oven for its final baking. The ground nuts act as extra waterproofing between fruit and pastry, as well as giving an agreeably nutty crunch to things.
Rhubarb Tart with Meringue Topping
800g (1¾ pounds) rhubarb
150g (5oz) sugar
250g (8oz) piecrust or puff pastry
2-3 tablespoons ground almonds or hazelnuts
2 teaspoons cornflour/starch
150 ml (generous ½ cup) crème fraîche or light cream
3 egg whites + a pinch of salt
150 g (5 ounces) sugar
- Trim the rhubarb, cut in 2-cm (1-inch) chunks and put them in a bowl. Sprinkle with 150 grams (5 ounces) of sugar, mix up well and leave to macerate for several hours or overnight until it releases most of its juice. Stir occasionally to make sure the sugar is well distributed.
- When you’re ready to make the tart, tip the rhubarb into a colander set over a bowl. Reserve the juice.
- Heat the oven to 400 degrees F (200 degrees C).
- Roll out the pastry and settle it into a 30-cm (12-inch) quiche pan with removable base.
- Prick the pastry with a fork and scatter a thin layer of ground nuts in the bottom.
- Arrange the rhubarb on top of the nuts.
- Bake for 20 minutes or until the pastry is beginning to color and the rhubarb is lightly cooked.
- Measure out 125ml (half a cup) of the reserved juice and mix in the cornstarch, stirring till smooth.
- Add this to the egg and crème fraîche, whisking well together till smooth.
- Remove the tart from oven and pour the mixture over the fruit.
- Return the tart to oven and bake for a further 15-20 minutes or until the custard is lightly set.
- Beat the egg whites with a pinch of salt until stiff, add 5 ounces (150 grams) of sugar and continue beating till stiff and glossy and you could turn the bowl upside down without the whites falling out.
- Remove the tart from oven and reduce the temperature to 170C (325F)
- Spoon the meringue mixture over the top, fluff it up with a fork and return the tart to the oven for another 15-20 minutes or until the meringue is firm and very lightly coloured.
- Cool the tart on a rack. Serve at room temperature for maximum flavor.
[A version of this article appeared first on Zester Daily.]