Really, really important.

AppController.php

/**
     * @Route("/teapot/brew/{slug}");
     */
    # THE MOST IMPORTANT METHOD ON THIS APPLICATION
    public function teapotAction($slug = '') {
        $response = new Response();
        if ($slug != 'tea') {
            $response->setStatusCode(Response::HTTP_I_AM_A_TEAPOT);
        } else {
            $response->setStatusCode(Response::HTTP_OK);
        }

        return $response;
    }