There have been de’os that took expansive views of the minhag, such as the Aruch Hashulcha saying “rice and beans and `anything else in the world”, and there is the school of Havu delo losif aley. Even the Rema (sourced to Maharil) lists some spice seeds as exempt. From the latter view, you can exclude from the issur anything native to the Americas, which were not known at the time of the gezerah. As an Askenazi in EY the choices of oil, l’mashal, are the non kitniyot olive, nut, and palm, all rather pricey, and the palm of questional health. The reasonably priced stuff is corn, soybean canola and sunflower. Corn and sunflower is native American. I use sunflower, and would use corn if I lived less in fear of my wife and other wagging tongues. There are also indications that the original parameter was dried kitniyot cooked into porrige, and that in the green state, there was no issur, such as fresh green peas, green beans, and say, CORN ON THE COB. Lastly, and this is perhaps exportable to the What to East on Pesach thread, Reb Moshe ztg”l ridiculed the inclusion of peanuts, and peanut oil was marketed by Rokeach in the 60s. Peanut butter (home made) and jelly on machine matzo is a real comfort food.
