Custom checkboxes with checkbox under text

I'm trying to have custom inline checkboxes with the text aligned above the checkbox. The checkbox has to be horizontally centered compared to the text. It should look like this:

I have tried to add the <br/> tag and moved the text over the control like this:

  <label class="custom-control custom-checkbox">
    <span class="custom-control-indicator"></span>
    <span class="custom-control-description">Check this custom checkbox</span>
    <br />
    <input type="checkbox" class="custom-control-input">
  </label>

without success... you can see the failed plunker here.

This plunker is the normal inline checkboxes of bootstrap v4