Condition only inside join in query

I'm trying to do a query in Symfony where I want find lunches for a day just for a specific employee. I really can't image it will be that hard, so I hope there is a simple answer.

The different tables in the DB are single_day, lunches and employees. A single day can have many lunches from different employees connected to it. In the rest API this will be the url that accomplish this: https://example.org/api/day?employee=728

In SQL this simple query solves it:

    SELECT * FROM hs_morning.single_day as single_day
    LEFT JOIN (SELECT id as lunch_id, vegetarian, employee_id, single_day_id FROM hs_morning.lunch WHERE lunch.employee_id = 727) as lunch
    ON single_day.id = lunch.single_day_id

I have this code in my repo and it returns all days as I want it to, but it does not filter out the lunches by other employees:

    public function findDayAndLunchesByEmployee($employee, $limit = 10)
        {
            return $this->createQueryBuilder('d')
                ->leftJoin('d.lunches', 'l', Expr\Join::WITH, 'l.employee = :val') // conditions here have no effect
                // ->andWhere('l.employee = :val') //this will prevent all days from being included (which I need) - so it does not work
                ->setParameter('val', $employee)
                ->orderBy('d.id', 'ASC')
                ->setMaxResults($limit)
                ->getQuery()
                ->getResult()
            ;
        }

So this is for example the result right now. My request on https://example.org/api/day?employee=728 is almost perfect, but I do not want the lunch for employee nr. 727 appear, only lunches for employee nr. 728:

[
    {
        "id": 118,
        "date": "2021-10-05T09:00:00+00:00",
        "lunches": [
            {
                "id": 2202,
                "vegetarian": false,
                "employee": {
                    "id": 728
                }
            }
        ]
    },
    {
        "id": 119,
        "date": "2021-10-06T09:00:00+00:00",
        "lunches": [
            {
                "id": 2199,
                "vegetarian": false,
                "employee": {
                    "id": 727
                }
            }
        ]
    },
    {
        "id": 120,
        "date": "2021-10-07T09:00:00+00:00",
        "lunches": [
            {
                "id": 2200,
                "vegetarian": false,
                "employee": {
                    "id": 727
                }
            },
            {
                "id": 2201,
                "vegetarian": false,
                "employee": {
                    "id": 728
                }
            }
        ]
    },
    {
        "id": 121,
        "date": "2021-10-08T09:00:00+00:00",
        "lunches": []
    },
    {
        "id": 122,
        "date": "2021-10-09T09:00:00+00:00",
        "lunches": []
    }
]

In other words this should not be in the response:

           {
                "id": 2201,
                "vegetarian": false,
                "employee": {
                    "id": 728
                }
            }
                    

EDIT: Thank you so much to @V-Light for a working solution. FYI: I also managed to achieve the same result with this piece of code (using ResultSetMappingBuilder and createNativeQuery):

public function findRecentDaysAndLunchesByEmployee($employee_id, $limit = 10)
{
    $sql = "SELECT * FROM single_day as single_day
    LEFT JOIN (
        SELECT single_day_id, employee_id, vegetarian, id as lunch_id
        FROM lunch WHERE employee_id = $employee_id
    ) as lunch
    ON single_day.id = lunch.single_day_id
    WHERE
    date BETWEEN '"
        . date("Y-m-d h:i:s", strtotime('monday this week 1am'))
        . "' AND '"
        . date("Y-m-d h:i:s", strtotime('friday this week'))
    . "'
    LIMIT $limit";

    $entityManager = $this->getEntityManager();

    $rsm = new ResultSetMappingBuilder($entityManager);

    //map query to SingleDay entity
    $rsm->addRootEntityFromClassMetadata('App\Entity\SingleDay', 'single_day');
    
    /**
     * map subquery to Lunch entity
     * 2. param: lunch alias
     * 3. param: parent query
     * 4. param: name of ORM relation
     * 5. param: new name for id of lunch in order to prevent conflict with id from single_day
     */
    $rsm->addJoinedEntityFromClassMetadata('App\Entity\Lunch', 'lunch', 'single_day', 'lunches', array('id' => 'lunch_id'));

    $query = $entityManager->createNativeQuery($sql, $rsm);
    return $query->getResult();
}