After all I found it, hidden in the "Git Repository view":
With Eclipse Mars (Egit Version 4.0.3) you can access the Stash via click on Project ==> Team ==> Stashes:
For me, the "AHA" moment was when I realized stashing (in EGit) happens at project level and not at file level. So I spent hours searching in the file context menu with no luck. Right click the project, and there it is...
