Please, please, please remove the onion? Or perhaps just get a decent sprite for it, but removing it seems reasonable.
When we get extra inventory space added and a means to make less valuable items spawn at different rates as specified in the mods, the onion can and should come back. As things are at current, it is all but worthless. It is more than worthless when you consider it could just as easily have been a better item like an omelet of some sort with 30x or more the food value. Considering that, I too think it should be removed for the time being.
If you just have that one problem with the mod, why don't you remove it yourself? RHM hasn't been seen on the forums since May 23rd, it's likely he's either vacationing or otherwise absent for a while.
Here's a substitute onion you could use. I'd told RHM he could use it, and I think he was going to but just hadn't got around to it yet. Just drop it inside the "items" folder of Dire Gourmand. It's not a great sprite, either, but it's a little closer to the style of Dredmor's item art.
While I'm somewhat concerned about RHM's continued absence, I am more concerned with the Extra Crispy proc, which has been brutalizing my character almost as much as Pumpkinns. The fact that the greasefires affect the character, while the damage they do is small, adds up, because greasefire goes off constantly* (and Extra Crispy does not provide adequate protection from it, I actually have a fair few points of conflagratory resistance and I'm still taking damage). Now, this is just a drawback which annoys me. That being said, it could also be taken as part of the flavor of Dire Gourmand - it does mention you're always hungry, after all. *Constantly here meaning, pretty much I can proc it again by the time it wears out.