poochi,
seems like ZY also like Hazel, can take to any type of food quite readily. She also prefered cooked eggs or scrambled eggs compared to dry egg yolk.
Michviv,
till now i also never add any seasoning, but i will choose vege with some flavour, like carrots, pumpkin, sweet potato. ZY also likes cheese, like ueno say, need to keep trying and vary the cooking style a bit, and they will eventually accept it.
Re: brushing teeth,
my first teeth toothbrush collecting dust, cos once ZY saw me brushing teeth, she prefers to brush herself, tho prob not clean! But i juz let her be.. so maybe u shld try to brush teeth together with them, they will be quick to mimic.