One of the easiest traditional British puddings to make at home, crumble can be made with a wide variety of fruits (or even with savoury fillings). As the days begin to lengthen and we patiently await the first thrums of spring, there are few desserts more appealing than classic rhubarb crumble. While even the simplest rhubarb crumble recipe will produce something delicious, a few simple tips can take this seasonally-appropriate British classic to the next level.
When Britain experienced a shortage of pastry ingredients, as a result of rationing during the Second World War, crumble became an economical alternative to pies. To save on flour, breadcrumbs and oats were often utilised in the dish, though most traditional crumble recipes have a topping of just flour and butter. Pairing rhubarb with ginger, this rhubarb crumble recipe has a topping which comprises flour (plain or self-raising is fine), butter, demerara sugar, rolled oats, and chopped almonds.
With a season that typically spans from late December to the end of summer, beginning with intense forced rhubarb from Yorkshire, with its vibrant Elephant & Castle pink hue, followed by the later arrival of the outdoor variety that’s woefully underappreciated. While the colouring is less social media-friendly, it’s still delicious; especially when slightly sweetened and baked into a perfect rhubarb crumble.
I love both, sliced into roughly 2cm chunks and bolstered by some fresh ginger, lemon juice, vanilla extract, cinnamon, a pinch of salt, and a little white sugar to temper the fruit’s sharpness without stripping it of its character. Stewing the filling before topping isn’t strictly necessary, but it gives the rhubarb a slight head start, helping the fruit to caramelise slightly and to give off some of its excess moisture – which can be left in the pan, drained slightly, or even drizzled over the crumble topping before or after cooking.
Using cold butter and chilling the crumble topping once prepared will also help to keep it firm as it cooks, ultimately producing a crumble with a gloriously crisp, biscuity lid. While packet crumble mixes seem convenient, they’re far less delicious than the homemade variety, which couldn’t be easier to make at home; even with just butter, flour, and sugar. A food processor will make life even easier, but the crumble topping is also simple to make by hand.
Custard is another absolute must when it comes to rhubarb crumble. Bird’s is fine, but the ginger’s warmth in this rhubarb crumble recipe is especially suited to simple, delicious cardamon-infused custard.
- 500 g rhubarb 500g (approx. 5 sticks)
- 100 g granulated sugar
- 2 tsp fresh ginger grated
- 1 tsp vanilla extract
- 1 tsp cinnamon
- 1 lemon
- A pinch salt
For the crumble topping
- 150 g flour
- 120 g unsalted butter cut into dice (needs to be very cold)
- 50 g demerara sugar
- 50 g chopped almonds
- 50 g rolled oats
For the cardamom custard
- 3 egg yolks
- 300 ml double cream
- 1 tsp vanilla extract
- 6 cardamom pods
- 1 ½ tbsp caster sugar
- 1 tsp cornflour
- Preheat the oven to 180C/gas 4.
- Begin by making the crumble topping, as this needs some time to rest in the freezer or fridge while you prepare the rhubarb. Add the flour and diced butter to a food processor and pulse until combined. If you don’t have a food processor, the ingredients can be mixed (literally crumbled) by hand in a large bowl.
- Once the butter and flour has an ideal crumble texture, gently incorporate the porridge and almond by pulsing just once or twice to avoid grounding the almonds or oats.
- Put the crumble topping into a zip lock bag or bowl and chill in the freezer for 10 minutes, or in the fridge for at least 20 minutes.
- Wash the rhubarb, remove the ends and slice each stick into approx. 2cm-1 inch pieces.
- Add the rhubarb to a suitable baking dish for the crumble. Top with the granulated sugar, ginger, vanilla, cinnamon, a pinch of salt, the lemon juice, and a tablespoon of water. Mix and place in the oven for 15 minutes, stirring once while cooking.
- As rhubarb gives off a lot of moisture, you may want to drain some of the liquid at the point, to prevent the crumble topping from getting soaked. Reserve it to use later.
- Pour your cold crumble topping over the rhubarb, making sure it’s all covered, but try to keep the topping fairly loose.
- Place the crumble tray in the oven for around 30-45 minutes, using a baking tray as an extra support to collect any juices that escape.
- Once golden, remove from the oven, rest for five minutes and serve with custard (or cream, if you really must). Optionally drizzle some of the excess rhubarb juice from cooking over the crumble.
To make the cardamom custard
- While the crumble is baking, prepare the custard by removing the cardamom seeds from their pods and lightly crushing with a pestle and mortar, or the back of a spoon. Add to a small saucepan with the cream and vanilla extract, and heat until steaming but not boiling.
- Remove from the heat and cover the pan, allowing the cardamom to infuse for 20 minutes.
- Whisk the egg yolks with the sugar. Once incorporated, add the flour and mix well. Pour some of the cardamom cream into the eggs (approx. one ladle) and whisk to combine. Slowly add the rest of the liquid to the bowl and whisk until completely incorporated.
- Strain the liquid back into the pan and cook over low heat, whisking almost constantly, until the custard is thick. It’s absolutely crucial to cook over a low heat without rushing this stage to avoid scrambling the egg yolks. If the custard does become clumpy, it may be salvageable by instantly removing from the heat and whisking an ice cube or two into the pan.
- Once prepared, serve as quickly as possible to prevent a thick skin from forming.