Inline template with Drupal 8 and Twig

Example 1. Basic inline template

    $output[] = [

      '#type' => 'inline_template',

      '#template' => '{{ yourvar }}',

      '#context' => [

        'yourvar' => 'The Value',

      ],

    ];

    return $output;

Example 2. Display a basic value and a raw HTML

    $output[] = [

      '#type' => 'inline_template',

      '#template' => '{{ yourvar }} {{ yourhtml | raw }}',

      '#context' => [

        'yourvar' => 'Your Var',

        'yourhtml' => '<span style="color:red;">Your HTML</span>',

      ],

    ];

    return $output;