I don't know if have these in Canada, but we have ready-made cartons over here - so you just open the carton, pour it into the bottle & it's ready to use.......then you just warm it up if that's what your LO likes (we're lucky, Olivia will take it at any temperature). They do cost a bit more than making the bottle from powder, but we only use maybe 3 a week, so it really isn't too expensive.