Press your fingernail into the base of the asparagus; if your nail easily makes a mark, then that indicates the tender spears. Chop off the tough portion of the spear.
Peel the skin from the bottom 4-cm of the spears with a peeler.
Add salt and vegetable oil to boiling water. Add both the chopped off end and the peels.
First dunk the base of the asparagus into the boiling water, then immerse the entire spear. Drain, then rinse in chilled water, then they're ready.
Do not give the nail test to the asparagus at the supermarket!
With freshly harvested asparagus, the tender spear is the portion that breaks off easily. There's no need to peel the skin from the base.
To store the asparagus, wrap the base of the spears in a wet paper towel, then wrap in a plastic bag, and store upright in the vegetable compartment of your refrigerator.
Story Behind this Recipe
I saw a chef parboil the base of the spears, so I also added the peeled skin.The flavor is nicely absorbed and seals in well with a drop of vegetable oil.
The parboiling time depends on the freshness and time of harvest of the asparagus, but about 1.5 to 3 minutes should do. If the skin starts to come off, you've boiled them too long. (Early harvest asparagus is tender and late harvest asparagus is a bit fibrous. I recommend using the tough parts in potage.)