could do something in your sleep idiom
梦里也能做（表示因为常做所以可以非常容易地做某事）
If you could do something in your sleep, you can do it very easily, usually because you have done it so often.
I've made this recipe so many times I could do it in my sleep now. 我做这个食谱很多次了，现在我在梦里也能做。