Yes, her kids should leave the nest knowing how to cook and bake...those are good life skills. But she's not doing it for that reason...she's doing it to make things "better" for HER, not because her kids should exit the nest knowing those skills. Is she also making sure they know how to keep a budget, do laundry, take care of basics on a car, spot an online or phone scam, talk through problems, understand and practice safer sex, and keep a reasonably clean, organized home? If so, will she only being those things, too, because she won't be "hated as a mother-in-law"?
Way to make it all about you, idiot lady.