Manzanillas are picked on the younger side, hence their light color. (Olives turn darker as they ripen—all of them start out green.) Naturally brine cured for months, the flesh is left firm. They have pits, a good sign when you're looking for olives. Pitted olives have often suffered under a violent machine that bruises their flesh, making them mushy and creating off flavors.
Manzanillas are the martini olive par excellence. Rinse the olive before you add it to a drink for clean flavor, or leave as is for fuller flavor. Throw in some brine if you want to make it dirty. Eaten on their own, I serve them rinsed and dressed with fresh extra-virgin olive oil—especially a nice Spanish one like Marqués de la Valdueza—garnished with fresh lemon zest.
To store, refrigerate and add a couple thin slices of lemon to the top of the brine after opening. The olives will last for months and months.