Peel the Onions and slice them into ⅛-inch-thick rings. Blanch them in a small saucepan of lightly salted boiling water for just a few seconds, then immediately drain and run under cold water.
Return the onions to the (empty) pan and add the cumin, oregano, garlic, vinegar, and sugar. If the onions are not completely covered, add some water to the pan. Bring to a boil, then immediately remove the pan from the heat and pour everything into a bowl to cool. These should be made at least a couple of hours ahead of time and set aside for the flavors to develop. Taste and season with salt and pepper. Store covered in the refrigerator for up to 2 weeks.
© 2004 John Ash. All rights reserved.