I am writing this because a few years ago I saw a recipe that called for olio and I couldn't find it anywhere in the grocery store. Like any normal person, I asked for help and the Piggly Wiggly stocker was sweet as could be, but I never did understand why he looked at me funny and talked even slower than most people do down here. I was too embarrassed to ask anyone again and just bought plain ol' margarine when I couldn't find the "Olio". (From the recipe I gathered it to be something similar.) Took me till just now to realize it wasn't a name brand, it's just plain ol' margarine, period. If I spare even one, 'young whippersnapper' from the confusion I felt than I have done well. Lord knows I certainly could have used the clue all those years ago! Now that I've been coming across it quite a bit in the handwritten recipes I got from Sister Weaver I HAD to look it up. Dictionary.com defines it simply as margarine. The word origin and history for oleo is stated as n. 1884 commercial shortening of oleomargarine. I've seen it written olio, oilo, and oleo, but no matter what you call it it's the same thing. When it's called for in the older recipes, I use a brand called Country Patties Vegetable Spread. It's wrapped in wax paper and sold in fat discs in the .......wait for it...... margarine section. (Shocker I know.) Not very many places sell it that I can find, but when I do find it, it's usually in the old school grocery stores or discount grocers. I ONLY use the Country Patties brand when I'm making the initial recipe as that is the style of margarine I remember the little old ladies from my youth using the most. I can honestly say it's generally the cheapest, which is probably why so many of them used it. Any margarine will do in its place so don't sweat it if you can't find it. Generally speaking, I try to stay as far away from margarine as I can, but when I can't afford butter you will find it in my fridge, usually Country Crock with calcium or Olivio if I'm honest. I will use margarine mostly for cooking purposes as I'm not a huge fan of the taste. If you really want to learn more about oleomargarine there is a book you can download from archive.org here. I have not read it myself yet, but it does seem interesting enough with chapters like History of Oleomargarine, Damage to the Dairy Industry, and Congressional Action. Its publication date is 1886 and as a result, is considered in the public domain. Not even gonna lie, this domestic history and historic foodie is going to start reading it pretty soon. Hope this post helps at least one of ya to keep from asking dreaded "Where do you stock the olio?" question, assuming this generation will even know what it is.