Populating a <select> input with Htmx

1

last night I saw a video on YouTube: CakeFest 2024 HtmxHelper The revival of JsHelper by Juan Diaz Gonzalez

After installing the plugin from Github and playing around with it, I have a question regarding the response from the controller.

I have three tables:
Worldcuisines with fields “id” and “name”
Nationalcuisines with fields “id”, “name” and “worldcuisine_id”
(Regionalcuisines with fields “id”, “name” and “nationalcuisine_id”)

Nationalcuisines is associated to Worldcuisines via (regionalcuisines is associated in the same way to nationalcuisines)

        $this->belongsTo('Worldcuisines', [
            'foreignKey' => 'worldcuisine_id',
            'joinType' => 'INNER',
        ]);

The form looks like this:

                    <?= $this->Form->control('worldcuisine_id', [
                        'options' => $worldcuisines, 
                        'empty' => true,
                        'hx-trigger'=> "change",
                        'hx-get' => $this->Url->build(['controller' => 'Nationalcuisines', 'action' => 'fetchNationalcuisines']),
                        'hx-target'=> '#nationalcuisine-id',
                        ]) 
                        ?>
                    <?= $this->Form->control('nationalcuisine_id', [
                        'hx-trigger'=> "change",
                        'hx-get' => $this->Url->build(['controller' => 'Regionalcuisines', 'action' => 'fetchRegionalcuisines']),
                        'hx-target'=> '#regionalcuisine-id',
                        'empty' => false,
                        'options'=>[__('Please select a worldcuisine')],
                        ]) 
                        ?>
                    <?= $this->Form->control('regionalcuisine_id', [
                            'empty' => false,
                            'options'=>[__('Please select a nationalcuisine')],
                            ]) 
                    ?>

The method in NationalcuisinesController:

    public function fetchNationalcuisines()
    {
        $this->autoRender=false;
        if (!$this->request->is('htmx')) {
            //do something, if it is no htmx request
        }
        $worldcuisine_id = $this->request->getQuery('worldcuisine_id'); 
        $nationalcuisines = $this->Nationalcuisines
            ->find()
            ->select(['id','name'])
            ->where(['worldcuisine_id'=>$worldcuisine_id])
            ->all();
        $options="<option>".__('No nationalcuisines to select')."</option>";
        if (count($nationalcuisines)>0) {
            $options="<option>".__('Please select a nationalcuisine')."</option>";
            foreach ($nationalcuisines AS $nationalcuisine) {
                $options.= '<option value="'.$nationalcuisine->id.'">'.$nationalcuisine->name.'</option>';
            }
        }
        echo $options;
        exit();
    }

This works for me, but I´m wondering if there is any other way to return the “$options” to the form. Maybe as json?
I did not find anything in the documents (maybe I did not enough research?).
Any hint or link to the documents would be helpful.