Yii 2.0 Widget element options

So I have a widget of listView that displays list of text

echo Menu::widget([
                   'options' => ['class'=>'nav navbar-nav side-nav'], 
                   'items'   => [
                       ['label' =>'Dashboard', ],
                       ['label' => 'Products'],
                   ]
                ]);

When I open browser , the result is :

<ul class="nav navbar-nav side-nav">
   <li>Dashboard</li>
   <li>Products</li>
</ul>

How do I add html element inside the <li> like below :

<ul class="nav navbar-nav side-nav">
     <li><i class='fap fap-dashboard'>Dashboard</i></li>
     <li><b class='fap fap-product'>Products</b></li>
 </ul>

by using widget ?

I have tried putting another item element beside label, but it instead created another <ul> element, and I also tried using 'options' beside label, and it instead change the li attribute (not creating inside it)

For reach you goal you need set encodeLabels property to false (see). Code like this(it is work code):

 Menu::widget([
                'options' => ['class'=>'nav navbar-nav side-nav', 'format' => 'raw'],
                'encodeLabels' => false,
                'items'   => [
                    ['label' => Html::tag('i', 'Dashboard',['class' => 'fap fap-dashboard'])],
                    ['label' => Html::tag('b', 'Products',['class' => 'fap fap-product'])],
                ]
            ]);