but recipes insist on calling for simply "1 onion" or for an onion that is small, medium, or large, or for it measured by cups with no mention of how many onions you should put on your shopping list.

One large raw onion has only 63 calories ... the root end of the onion until the rest has been sliced or chopped. 1. Preheat oven to 400°F. 2. Peel the onions and cut into lengthwise quarters.