is this right according to BEM?

bem-test.html

<aside class="sidebar">
  <nav class="menu">
    <div class="menu-item">
      <a href="" class="menu-item__link">
        <span class="menu-item__icon">
          <i class="ion-ios-home-outline"></i>
        </span>
        <span class="menu-item__text">
          Home
        </span>
      </a>
    </div>
  </nav>
</aside>

I'd tweak it a little bit...

<aside class="sidebar">

  <!-- 
    These two (likely) have a parent/child relationship
    A `menu` is a list of `menu__item` elements.
    A `menu__item` is just a container for whatever you choose to put inside.

    So the `menu` block is responsible for laying out your menu.
  -->
  <nav class="menu">
    <div class="menu__item">


      <!--
        `menu-link` is where you visually style individual links.
        It's got two child elements: `menu-link__icon` and `menu-link__text`.
      -->
      <a href="" class="menu-link">
        <span class="menu-link__icon">
          <i class="ion-ios-home-outline"></i>
        </span>
        <span class="menu-link__text">
          Home
        </span>
      </a>


    </div>
  </nav>
</aside>

so I can go from an element (menu__item) to a block again (menu-link)?

@luisrudge absolutely, you just want to keep any nested blocks independent of their parents (i.e. reduce the depth of applicability). So you don't want styles from the menu block leaking through to menu-item.

awesome. Thanks!