Ingredient

Parsnip

A parsnip is a root that stores its energy as starch through the summer and converts a good deal of it to sugar when the weather turns cold. That conversion is why parsnips are a midwinter vegetable, why they caramelise so readily, and why one bought in August is a pale imitation of one bought after the first frost.

Why frost matters

Parsnips accumulate starch as they grow. When the soil temperature drops, the plant converts some of that starch into sugars, which lower the freezing point of the cell contents and protect the root from frost damage. It is antifreeze, and it happens to be delicious.

The practical consequence is that a parsnip lifted after cold weather is markedly sweeter than one lifted in autumn, and that sweetness is what makes it brown so well. The sugars caramelise at the surface during roasting, and there is far more sugar available to caramelise than in a carrot or a potato.

It is also why parsnips burn more easily than other roots. The same sugar that browns beautifully will go past brown to bitter quickly at the edges, and thin ends catch long before thick ones.

Roasting them properly

The most common failure is a parsnip that is soft and pale rather than crisp and mahogany.

1. Peel them. Parsnip skin is thin but tough and slightly bitter, and unlike a carrot it does not improve the dish.
2. Cut them into even pieces, and cut the thick end into more pieces than the thin end so that everything is roughly the same thickness. Quartering the fat end lengthways and halving the thin end usually does it.
3. Deal with the core if the parsnip is large. In a big old parsnip the central core is noticeably woodier and more fibrous, and cutting it out is worth the minute it takes. In young or medium parsnips there is no need.
4. Parboil for a few minutes if you want maximum crispness, then drain and let the steam escape completely. The dry surface is what crisps.
5. Toss in fat — goose fat, beef dripping or oil — and get them into a properly hot oven on a hot tray in a single layer with space between them.
6. Roast until deeply browned. Turn them once. Add honey or maple only in the last few minutes, or the sugar will burn well before the parsnip is cooked.

Other things to do with them

• Parsnip purée, simmered in milk and blended with butter. Sweeter and more perfumed than potato, and excellent under game or duck.
• Parsnip soup, with apple, curry spice or both. It takes warm spices better than any other root — cumin, coriander, curry powder and cinnamon all work.
• Parsnip crisps, sliced with a peeler and fried or baked.
• Roasted with the Sunday joint, alongside potatoes, though parsnips need less time and should go in later.
• Grated raw into a slaw, which very few people try and which works well against something sharp.
• Parsnip cake. Like carrot cake, and arguably better — the sweetness and the slight spiciness suit it.
• In a mash with potato, a third parsnip to two thirds potato.

Choosing and keeping

Size

Small to medium are sweeter and have less woody core. Very large parsnips can be fibrous through the middle.

Firmness

Hard and heavy. Bendy parsnips have lost water and will be disappointing.

Colour

Pale cream. Brown patches or soft ends mean it is going.

Season

Best from the first frosts through to early spring. Out of season they are stored crop and less sweet.

Storage

Weeks in the fridge in a bag. They dry out fast if left uncovered.

A caution

The leaves and stems of the parsnip plant can cause skin reactions in sunlight. This matters if you grow them; it does not affect the root you buy.

Common questions