The first occasion of edible people within Oz itself occurs in Emerald City, with its village of Bunbury (quite possibly named after the imaginary relative from The Importance of Being Earnest, but I don't believe there's ever been actual confirmation on this), home to a large number of rather aristocratic baked goods. Dorothy pays a visit there that starts out friendly, but goes sour when Toto, on a dare, eats a few of the citizens (and given what we learn about Toto in Tik-Tok, he really should have known better). There's no indication as to how the people of Bunbury came into existence, but since the neighboring town of Bunnybury was established by Glinda, and the book also credits her with setting up the Cuttenclips' village, I don't think it's too far-fetched to say that Glinda granted some life-giving ovens and a plot of land in her Quadling Country to an eccentric baker. Incidentally, one of the advertising pamphlets that Ruth Plumly Thompson wrote for the Royal Baking Powder Company was called "Billy in Bunbury," but since I haven't read it, I couldn't tell you whether it's about the same Bunbury. Her other advertisements for the company did feature live food people, including the Jinn of the Gelatin Isles. I'm not sure how many baking products Royal makes today, but I know their gelatin is still available as a cheaper alternative to Jell-O.
Speaking of Thompson, she brought in a candy giant named Bangladore as a minor character in her first Oz book, Royal Book. He's made out of taffy, with sour ball eyes and a chocolate coat. Her second book, Kabumpo, introduces another bit part, the King of the Soup Sea, who is made out of soup bones with a cabbage for a head and a soup bowl for a crown. He is a quite friendly ruler, whose job is to keep his sea of soup stirred and seasoned, and to present rolls to visitors.
In John R. Neill's Wonder City, there's an army of giant chocolate soldiers living on a chocolate star in the sky above Oz. The soldiers are made out of the chocolate of the star itself, and they typically act in unison, all except for their general. The soldiers set out for the Emerald City on a silver cloud with a dark lining in order to conquer the capital of Oz, but Jenny Jump saves the city by setting up her Turn-Style in the city gate, which turns them all into toy tin soldiers. His next book, Scalawagons, shows the Lolly-Pop Village, located at the foot of Carrot Mountain in the Quadling Country, alongside the Singing Brook inhabited by water fairies and kelpies. The village itself is inhabited by the six industrious Lollies, each of whom is a different flavor (the text mentions Minty, Scotchy, Choco, and an unnamed lemon-flavored girl), and their lazy Pops. The Pops are actually now somewhat more active, since Tik-Tok knocked some sense into them with a mallet.
In Dorothy, Roger Baum brings in his own edible Candy Country, ruled by the Giant Royal Marshmallow. The cannibalistic tendencies of the candy people of Merryland seem to come into play again here, with Dorothy discovering that all foods EXCEPT marshmallow make the monarch sick. Incidentally, a letter from L. Frank Baum mentions that he was originally thinking of replacing the Garden of Meats chapter from Patchwork Girl with an encounter with the Marshmallow Twins, but he was presumably convinced by the publisher that the book was long enough without it. I wonder if these twins are related to the Giant Royal Marshmallow.