Helper/EmailHelper.php
protected function renderStringTemplate($template, $parameters = array())
    {
        $template = $this->environment->createTemplate($template);

        return $template->render($parameters);
    }
protected function renderStringTemplate($template, $parameters = array())
    {
        $template = $this->environment->createTemplate($template);

        return $template->render($parameters);
    }
Renders a string template

@param       $template
@param array $parameters

@return string