I like this manga but I'm worried about its future, considering that the WN and LN versions have been on hiatus for a long time. And this chapter has almost reached WN's last chapter before the long hiatus.
No. Zed is not the Prime Minister. Zed is of the same race as Zenia, the one the Prime Minister worship (see chapter 26).
The Prime Minister is an ordinary human. He worships Zenia, someone of the same race as Zed (see chapter 26).
Most of the readers who complained about this "cooking" part had never read WN. People who have read WN know that this part is very important for Mio's character development and for Mio's upcoming events (Mio meets "someone").