So, I have created a test user that is a member of the JIRA software user group and to one project. That is all. They can still see the cog, use the drop down, click on projects and see a list of all the projects.
I just want them to have access to the one project to which they have permissions, and they do only see that one project when they click on "projects" next to dashboards... it is just that they can click on that cog! They are NOT part of the Jira Administors group.