- As a cruciferous vegetable, kohlrabi is high in dietary fibre and many vitamins and nutrients, including vitamins C, vitamin A and vitamin K, potassium and manganese.
- Kohlrabi is grown all year round, but is at its best in the UK between July and November when the vegetable is golf ball, rather than tennis ball, sized.
- While the main part of the vegetable is the bulb, the leaves are also edible. Ensure the leaves are green (not yellow) for freshness and cook them as you would other leafy greens.
It may not be the most aesthetically pleasing vegetable, but looks are insignificant when it comes to kohlrabi's culinary capabilities.
This bulbous brassica, which comes in two varieties – white (actually a light-green colour) and purple – has been cropping up on menus far and wide over the last year, both as the main star and the support act.
With a sweet and mild taste and the texture of broccoli stems, kohlrabi lends itself to many cooking techniques: sliced thinly and served raw in a salad, pickled and used as a garnish, salt baked as a centrepiece, or roasted as a side.
“I love its versatility as a raw and cooked vegetable,” says Pratap Chahal, executive chef of London restaurant Flavour Bastard. “Cooked, it's closer to turnip; raw, it's in the field of cucumber mooli. We use it throughout the year, but it's best in the summer and autumn.”
Richard Bainbridge, chef-owner of Benedicts in Norwich, was introduced to kohlrabi 18 years ago by his German wife and features the vegetable in one way or another on his menu year-round – helped, no doubt, by the fact he also grows it himself.
“It's one of the most versatile vegetables there is,” he says. “You can make a savoury sorbet out of it, salt bake it or peel it right down and serve it whole. This vegetable is incredible.”
Pratap Chahal, executive chef of Flavour Bastard in London, includes kohlrabi in his octopus dish with passion fruit, avocado, chipotle, and crunchy corn: “This is a cold dish of octopus marinated in passion fruit and chilli and served with avocado puree and a raw kohlrabi-shallot salad dressed with a chipotle dressing. After steaming the octopus, we slice and smoke it gently. Then it's mixed with a passion fruit-chilli-ginger marinade. We then do a puree of avocado with a little salt and a fine julienne of kohlrabi and shallot with coriander. To finish, we dress the kohlrabi with a chipotle dressing and sprinkle toasted Peruvian corn over the dish. A sweet and musky crunchy element, it's there for texture and to provide a delicate flavour which doesn't clash with the octopus. The shallot also offsets the sweetness of the kohlrabi by adding a little pungency, so you have a dish that's sweet, sour, salty, spicy and crunchy.”
Richard Bainbridge, chef-patron at Benedicts in Norfolk, includes kohlrabi in his main course of salt-baked heritage carrot: “We salt bake the carrots, which have been stored in sand since the winter, in a malted Norfolk barley salt crust, then we make courgettes into a flower shape, cure them in cumin and seal them off to get a crispy edge on them. The kohlrabi is cut with a Japanese mandolin, so it comes out in big strips, which we then season with a bit of salt and sugar and roll the strips back on themselves. We slowly roast the kohlrabi on one side in Norfolk rapeseed oil, until it steams all the way through. You get this crispy top and sweet steamed kohlrabi underneath. The dish is quite sweet, but kohlrabi's got a slightly bitter edge to it, so when you roast it off you get this almost scorched bitterness from the roasted side and sweet, earthy kohlrabi flavour coming through at the end which counter-balances the sweetness of the carrot. The carrot, courgette and kohlrabi is also served with Norfolk peas, a little bit of pickled carrot, malted barley that is cooked in kohlrabi and carrot juice, bronze fennel and then finished with a beer sabayon.”
Hugh McGivern, head of food development at All Star Lanes, turns kohlrabi leaves into a garnish for steamed red mullet: “I mix plain flour, cornflour, icing sugar and smoked chilli paprika with a little sparkling water to create a thin batter. Take kohlrabi leaves and sandwich them together with some basil pesto or black olive tapenade before dipping them in the batter and deep-frying for one to two minutes until golden. I use the drained leaves as a garnish for a steamed red mullet dish. The earthiness of the meaty fish fillets is a good match for the crispy kohlrabi leaves and the hit of basil pesto or olive tapenade you get when biting into them. It's a real hit and unusual because people often veer away from what is a beautiful vegetable.”