How to make rhubarb crumble – recipe

The humble crumble is rubbly heaven, and a real cinch to perfect. When I last set finger to keyboard on this subject, I claimed that anyone can make a decent crumble. Age has made me slightly less generous; we’ve all chewed our way through dusty scatterings of flour and stodgy doughs that, delicious as they may have been, could, honestly, also have been a lot better. Fortunately, perfection here is not difficult.

Image Credit: the Guardian [Felicity Cloake]

Prep 10 min. Cook 40 min. Serves 6-8. 800g rhubarb. 40g demerara sugar, or white sugar. A pinch of spice (ginger, cinnamon – optional). For the crumble topping. 150g plain flour. 75g demerara sugar. ¼ tsp salt. 75g ground almonds. 170g chilled unsalted butter. 25g skin-on almonds, or other nuts (optional). Nigella reckons rhubarb is “the best crumble in the world”, but the recipe can, of course, be adapted to other fruit, according to both taste and season (or, indeed, to frozen fruit at any time of year); for other options see step 8. The fruit will be hidden underneath the topping, so crumble is also a great use for less lovely thicker or greener stems of rhubarb, underripe stone fruit, gluts of apples, etc.

Image Credit: the Guardian [Felicity Cloake’s rhubarb crumble 01a. Some rhubarb in stalk mode.]

Put the flour in a large bowl. I’ve used plain for simplicity’s sake, but crumble will work with most flours, with the proviso that some will absorb more moisture than others and as a result give less crisp results – I particularly like rye, spelt or other nutty-flavoured flours. And note that you can substitute gluten-free flour with no other changes. Add the sugar, salt and the ground almonds to the flour (again, other ground nuts will work well instead, or feel free to leave them out entirely and simply make up the difference with extra flour).

Image Credit: the Guardian [Felicity Cloake’s rhubarb crumble 03a. Put the flour in a large bowl, add the ground almonds, sugar and a pinch of salt, and mix to combine]

Coarsely grate or finely dice the butter, then rub it into the dry ingredients with your fingertips, until the mix is fairly well combined but still lumpy – you shouldn’t be able to see butter, but nor should the mixture be homogenous. Wet your hands with cold water, then briefly toss the dough until it’s in small clumps. Spread these out on a lined baking tray and put in the freezer for 10 minutes, or chill for at least 20 minutes and up to 48 hours. (Alternatively, you can work well ahead and keep batches in the freezer for later use; you can bake the crumble mix straight from frozen.).

Image Credit: the Guardian [Felicity Cloake’s rhubarb crumble 04a. Add the grated butter, rub it in until the mix looks like breadcrumbs, then spread out on a lined tray and chill]

Meanwhile, heat the oven to 200C (180C fan)/390F/gas 6. Wash the rhubarb, then trim away any leaves or discoloured ends and chop the stalks into roughly 3cm lengths. Put these, with the moisture from washing still clinging to them, in a medium baking dish just big enough to hold all the rhubarb (if your dish is too large, you’ll run out of topping). Pour the demerara sugar evenly over the rhubarb and toss well to coat (you can use white or soft brown sugar, if you prefer, with the caveat that the darker the sugar, the darker the result. I sometimes substitute a few spoonfuls of syrup from the jar of stem ginger, or honey). Add a pinch of spice, if you like – ginger or cinnamon work well, as does grated orange zest.

Image Credit: the Guardian [Felicity Cloake’s rhubarb crumble 06wash the rhubarb, then chop it into 3cm lengths. Toss with sugar and optional spices to taste.]

Tip the chilled crumble mix on top of the fruit, level it out reasonably evenly, then bake for about 30 minutes, until starting to colour. Meanwhile, roughly chop the extra nuts, if using, then, when the half-hour is up, scatter these on top of the crumble and bake for 10 minutes more, until the topping is crisp and golden and the fruit below bubbling. Serve with custard, cream or ice-cream. Crumbles are very forgiving – you can use the same weight of apples (cooking, dessert or a mixture), pears, plums, mangoes, pineapple … in fact, you can use almost anything you have, adjusting the sugar according to the sweetness of the fruit. Juicier fruit such as berries might benefit from being tossed with a tablespoon of cornflour before cooking, to help absorb those juices. You can also use frozen fruit, in which case there is no need to thaw it before baking.

Image Credit: the Guardian [Felicity Cloake’s rhubarb crumble 07a. Tip the rhubarb into a baking dish in which it will fit snugly, then scatter the cold crumble mixture evenly on top]

Adjust extras to suit the fruit. Tropical fruits would suggest adding lime zest and nutmeg to the fruit mix, and perhaps some flaked coconut in the crumble topping. Plums, meanwhile, are lovely with orange zest and star anise (remember to fish out the latter when you serve!) and apples cinnamon, nutmeg, vanilla and walnuts. A dash of booze, such as rum, brandy or amaretto, will rarely go amiss, either.