menu_block_title
What this module does
This module adds an option to system menu blocks which when active will show the active menu item's parent as a link in the block's title. This makes for useful sidebar menus where the block title is a link back to the current item's menu parent.
How to configure it
Once installed, place a system provided menu block or create and place a menu_block module provided menu block. This module works best with a block starting at menu level 2.
When editing the configuration for that block in the UI you should notice a checkbox at the bottom of the page with the following label: "Block title as menu link parent"
Check this option and make sure the block title is not hidden and save the block. When you visit the page with this block placed on it you should see the title of the block is now the parent item of the menu.
In the wild
Some examples of this module in use: