Always_ask-Questions: “I can see if someone davens at 10a AND slowly with kavana – that he would need a piece of cake before that. I saw a quote fomr Kotzker who answered his student, a grandson of R Akiva Eger, how to justify the practice to his zeide: Rambam says that…”
I have seen that story in the sefer Emes Ve’emunah, but it had nothing to do with eating before davening. It had to do with davening late.
In fact, and I think it also says this in the above sefer, Kotzker chassidim did not eat at all before Shachris, which is why even when they davened very late they would make sure to finish before shkiah and then eat something so that they wouldn’t have the feeling that they did something good by fasting all day.