It may be helpful to share tips that some of us have figured out over time. To get the ball rolling: Onion skins peel without splintering if they are moist. Soak papery-skinned onions in cold water for ten minutes or more before peeling. Onion skins come off more easily if you start at the end where the greens were, not the root end. If you want a bit more security when slicing them, leave the peel attached to the root, halve the onion pole to pole, then grab the peel to help you hold the half in place but farther from your knife as you near the root end.
After you’ve peeled a navel orange and are removing the pith, strip it starting at the stem end. It comes off readily compared to starting at the navel. Same goes for other citrus.
The “snot” contains a lot of the flavor in tomatoes, so either don’t seed them, or sieve the seeds and return the goo to the food.
Snapping asparagus stalks wastes a fair amount. If you are frugal, slice off the white, hard end, but keep the green unless it feels very woody.
IF you want to wash mushrooms, don’t do it until just before you use them, or they’ll get mushy faster. DO remove the stems of shiitake mushrooms. You can save them for making stock, but they are too tough for most cooking purposes.