Hi Jason,
To add a Favorites list to Word's Quick Access Toolbar, you can right-click on the list, then you can see the
Add to Quick Access Toolbar option.
Note that if you right-click on the icon of a list, only the list itself will be added to the Quick Access Toolbar; If you right-click on the ribbon name (Word Favorites), all your lists will go to the toolbar.
This is how it looks:
Hope this can help you.
Amanda