How can I create submenus in off canvas in Foundation 6?
I found this handy building block, but it doesn't feature submenus in the LHS off-canvas menu.
I'd like a slide-in submenu like this one (this is Foundation 5).
I believe you're looking for Foundation 6's Drilldown menu. See link below and code snippet from page.
<ul class="vertical menu" data-drilldown>
<li>
<a href="#">Item 1</a>
<ul class="vertical menu">
<li><a href="#">Item 1A</a></li>
<!-- ... -->
</ul>
</li>
<li><a href="#">Item 2</a></li>
</ul>