Sweet Potato

Firm sweet potatoes with orange flesh. Sweeter and moister than a regular potato, and they behave differently in heat — the starch converts to sugar as they cook, so slow dry heat gets far more out of them than boiling does.

Roast them in wedges, bake them whole and split them open with butter, or mash them into a curry where they will thicken it as they go. They also make a shakarkandi chaat with lime, chaat masala and a lot of black salt, which is worth the effort.

Look for firm tubers with unbroken skin. Soft ends and dark sunken patches both mean rot that will spread through the whole thing.

Cool, dark, dry, and out of the fridge — cold makes the centre hard and no amount of cooking softens it afterwards.

Do not wash them before storing; the soil that comes with them is protective.

Two weeks stored properly.