Maintaining stereo mix - novice question

I created a stereo mix wav file. I now want to add one more track to the mix. I accidentally deleted the raw mix tracks and all that remains is the single stereo wav file. I want to add the track to this mix without losing the stereo. I am a novice so go easy on me. How do I import the stereo file into a new cubase project, add the additional track and then mix them together and still maintain the stereo nature of the mix? Thanks in advance.


File > Import > Audio opens a dialog, where you can choose the audio file, you want to import.

Then you will just mix it the same way, as other tracks (from the technical point of view; but your situation would be worse, because of Reverbs, Compresors…, if you already used them for the original mix; from the soundengineer point of view).

Once you are done, use File > Export > Audio Mixdown.