As a general rule, when it comes to pickling, it should be done when the produce is at its peak and is therefore cheaper. When it comes to pickling asparagus, I don't really follow that rule, though. I usually pickle different varieties of asparagus at the start of the season to preserve the first crop, which have skins that are really succulent and do not need peeling. Pickled asparagus is great as part of an antipasti platter or added to salads when the fresh stuff is out of season.
Preheat the oven to 275 degrees.
Wash three 10 ½-ounce glass jars and make sure they are odor-free and dry. Lay a jar on its side and measure the asparagus next to it, chopping off the bottom part of the stalks to fit the jars. (Discard the scraps or use to make asparagus soup or a salad.)
In a saucepan, bring salted water to a boil over high heat and set up an ice bath. Quickly blanch the asparagus, then drain and refresh in the ice bath. Once cool, take, out and pat dry, then place into the jars, crown side up.
Put the vinegars in a saucepan and bring to a boil, then let cool. Divide the spices, garlic, and shallot among the jars and pour over the vinegar, making sure the liquid completely covers the asparagus.
Screw on the lids, place on a baking sheet, and put into the oven for 10 minutes. Label and store in your cupboard for at least 1 week before using, but 3 months is better. Unopened jars will keep until the next season. Once opened, store in the refrigerator.