data.json

{
  "menu": {
    "home": [
      {
        "label": "title1",
        "iconClass": "icon1"
      },
      {
        "label": "title2",
        "iconClass": "icon2"
      }
    ]
  }
}

template.hbs

<script id="menu-item-template" type="text/x-handlebars-template">
  {{#each menu}}
    <nav class="{{@key}} current"> {{! it prints home }}
      {{#each @key}} {{! this should iterate home, but doesnt works }}
        <div class="menu-item">
          <span class="icon {{iconClass}}"></span>
          {{label}}
        </div>
      {{/each}}
    </nav>
  {{/each}}
</script>