public function sendEmail() {
    $sent = Mail::send('mails.test', [], function ($message) {
        $message->to('xxxxxxx@windowslive.com','somename');
        $message->subject("Activate Your Account");
        $message->getSwiftMessage();
    });
    if ($sent === 0) {
        return redirect('/')
            ->withErrors('Failed to send activation email.');
    }
    return redirect('/')
        ->withSuccess('Mail was sent.');
}

MAIL_DRIVER=mailgun
MAIL_HOST=smtp.mailgun.org
MAIL_PORT=587
MAIL_USERNAME=postmaster@sandbox*****************************.mailgun.org
MAIL_PASSWORD=**********************
MAIL_ENCRYPTION=null

MAILGUN_DOMAIN=sandbox*****************************.mailgun.org
MAILGUN_SECRET=key-*****************************

Route::get('auth/send','AuthController@sendEmail');

<a href="{{action('AuthController@sendEmail')}}" class="btn btn-danger">Test mail</a>