Passing an array stdClass Object from custom module to template
I don't know why it was not working because after I've done a simple 

&lt;pre&gt;
    {{ dump(myvariable) }}
&lt;/pre&gt;


In order to check if the array was passed to the twig template, everything is working.

So the solution is in my-template.html.twig

{% for key, value in myvariable %}
    Key : {{ key }}&lt;br&gt;
    Date: {{ value.dateDebut }}&lt;br&gt;
    Societe : {{ value.societe }}&lt;br&gt;
{% endfor %}