Восстанавливаем объект из сессии

User.php

<?php

namespace App\Model;

use Illuminate\Database\Eloquent\Model;

class User extends Model
{
    public static function currentUser(): User
    {
        return self::reCreate($_SESSION['auth']);
    }

    private static function reCreate($obj)
    {
        $obj = (array)$obj;
        $newObj = new User();
        foreach ($obj as $k => $v) {
            $parts = explode(chr(0), $k);
            if ($k != '__PHP_Incomplete_Class_Name') {
                if ($parts[0] == $k)
                    $newObj->reCreatePrivate($k, $v);
                else
                    $newObj->reCreatePrivate($parts[2], $v);
            }
        }
        return $newObj;
    }

    private function reCreatePrivate($name, $value)
    {
        $this->$name = $value;
    }

}