AuthController.php

<?php
// When I try to sign in, I get TokenMismatchException 

namespace App\Http\Controllers\Auth;

use App\User;
use Validator;
use App\Http\Controllers\Controller;
use Illuminate\Foundation\Auth\AuthenticatesAndRegistersUsers;

class AuthController extends Controller
{
    /*
    |--------------------------------------------------------------------------
    | Registration & Login Controller
    |--------------------------------------------------------------------------
    |
    | This controller handles the registration of new users, as well as the
    | authentication of existing users. By default, this controller uses
    | a simple trait to add these behaviors. Why don't you explore it?
    |
    */

    use AuthenticatesAndRegistersUsers;

    /**
     * Create a new authentication controller instance.
     *
     * @return void
     */
    public function __construct()
    {
        $this->middleware('session.start');
        $this->middleware('session.errors');
        $this->middleware('csrf');
        $this->middleware('guest', ['except' => 'getLogout']);
    }

    /**
     * Get a validator for an incoming registration request.
     *
     * @param  array  $data
     * @return \Illuminate\Contracts\Validation\Validator
     */
    protected function validator(array $data)
    {
        return Validator::make($data, [
            'name' => 'required|max:255',
            'email' => 'required|email|max:255|unique:users',
            'password' => 'required|confirmed|min:6',
        ]);
    }

    /**
     * Create a new user instance after a valid registration.
     *
     * @param  array  $data
     * @return User
     */
    protected function create(array $data)
    {
        return User::create([
            'name' => $data['name'],
            'email' => $data['email'],
            'password' => bcrypt($data['password']),
        ]);
    }
}

HomeController.php

<?php 
// This one works as expected

namespace App\Http\Controllers;

class HomeController extends Controller 
{
  public function __construct()
  {
    $this->middleware('session.start');
    $this->middleware('session.errors');
    $this->middleware('csrf');
    $this->middleware('auth');
  }

	public function index()
	{
		return view('home');
	}

}

Kernel.php

<?php

namespace App\Http;

use Illuminate\Foundation\Http\Kernel as HttpKernel;

class Kernel extends HttpKernel
{
    /**
     * The application's global HTTP middleware stack.
     *
     * @var array
     */
    protected $middleware = [
        \Illuminate\Foundation\Http\Middleware\CheckForMaintenanceMode::class,
        \Illuminate\Cookie\Middleware\EncryptCookies::class,
        \Illuminate\Cookie\Middleware\AddQueuedCookiesToResponse::class,
    ];

    /**
     * The application's route middleware.
     *
     * @var array
     */
    protected $routeMiddleware = [
        'auth' => \App\Http\Middleware\Authenticate::class,
        'auth.basic' => \Illuminate\Auth\Middleware\AuthenticateWithBasicAuth::class,
        'guest' => \App\Http\Middleware\RedirectIfAuthenticated::class,
        'csrf' => \Illuminate\Foundation\Http\Middleware\VerifyCsrfToken::class,
        'session.start' => \Illuminate\Session\Middleware\StartSession::class,
        'session.errors' => \Illuminate\View\Middleware\ShareErrorsFromSession::class,
    ];
}

login.blade.php

@extends('app')

@section('content')
<div class="container-fluid">
	<div class="row">
		<div class="col-md-8 col-md-offset-2">
			<div class="panel panel-default">
				<div class="panel-heading">Login</div>
				<div class="panel-body">
					@if (isset($errors) && count($errors) > 0)
						<div class="alert alert-danger">
							<strong>Whoops!</strong> There were some problems with your input.<br><br>
							<ul>
								@foreach ($errors->all() as $error)
									<li>{{ $error }}</li>
								@endforeach
							</ul>
						</div>
					@endif

					<form class="form-horizontal" role="form" method="POST" action="{{ url('/auth/login') }}">
						<input type="hidden" name="_token" value="{{ csrf_token() }}">

						<div class="form-group">
							<label class="col-md-4 control-label">E-Mail Address</label>
							<div class="col-md-6">
								<input type="email" class="form-control" name="email" value="{{ old('email') }}">
							</div>
						</div>

						<div class="form-group">
							<label class="col-md-4 control-label">Password</label>
							<div class="col-md-6">
								<input type="password" class="form-control" name="password">
							</div>
						</div>

						<div class="form-group">
							<div class="col-md-6 col-md-offset-4">
								<div class="checkbox">
									<label>
										<input type="checkbox" name="remember"> Remember Me
									</label>
								</div>
							</div>
						</div>

						<div class="form-group">
							<div class="col-md-6 col-md-offset-4">
								<button type="submit" class="btn btn-primary">Login</button>

								<a class="btn btn-link" href="{{ url('/password/email') }}">Forgot Your Password?</a>
							</div>
						</div>
					</form>
				</div>
			</div>
		</div>
	</div>
</div>
@endsection