I think one can say сандвич here
The usual spelling would be сандвіч, with i: http://sum.in.ua/s/sandvich
I don't know if it's accepted here or not.
Ahh, that's not a real Ukrainian word.
It's not a real Ukrainian food!
I don't think "сандвіч" is ever used. "Бутерброд" is more common.
It gets 12,000 hits on Google and 38,000 on Yandex . . .