Asparagus used to be considered a spring vegetable, but it's now available year-round.
What is it? A vegetable that - like onions, garlic and leeks - belongs to the lily family. The different varieties are about the same length (16-18cm), but they range in diameter from thinner than a regular pencil to more than 1.5cm. Asparagus comes in green, white or purple.
What are the differences? Thinner spears are cheaper and less desirable because they have a higher skin-to-flesh ratio. Thicker spears are succulent and have a better flavour. White asparagus is made by denying the growing spears exposure to light, which prevents the production of chlorophyll. Purple asparagus is a more recently developed, sweeter variety.
How to choose: look for tightly closed tips. If the tips are starting to spread, the asparagus is old.
How is it available? Fresh, of course, as well as frozen and in cans or jars. While canned vegetables are frequently dire, white asparagus canned in Spain - specifically Navarra - is considered a delicacy.
What else? Old-fashioned cookbooks advise snapping off the ends of the spears because it was once believed the lower part of the vegetable - where the spear broke - was too tough to be consumed. To avoid the waste this entails, cut off the tough, woody ends then use a vegetable peeler to shave off the fibrous parts of the stalk.