Breakdown of К чаю бабушка разрезала тёплую булку и намазала на неё масло.
Questions & Answers about К чаю бабушка разрезала тёплую булку и намазала на неё масло.
К чаю is a very common Russian expression meaning for tea, with tea, or to go with tea.
The preposition к normally takes the dative case, so чай becomes чаю.
Here it is not about movement toward tea in a literal sense. It is an idiomatic way to say that something is prepared to be eaten or served with tea.
Russian word order is much more flexible than English word order.
Starting with К чаю puts that idea in the spotlight first: as for tea / for tea, grandma... In other words, it sets the scene or context before introducing what grandma did.
A more neutral order would also be possible, for example:
Бабушка разрезала тёплую булку и намазала на неё масло к чаю.
But the original sounds natural and gives к чаю a bit of emphasis.