WordPress pass data from php to an block

I am trying to pass data from a php array to my created Gutenberg block. I need this data to populate a select inspector control. Right now im using the wp rest api and fetching the data inside the array. However this method is very slow and I am wondering if there is a faster approach to getting this data. I only need the data when i create the inspector controls for the block.

let options = [];
    options.push({ value: -1, label: 'Select a template' });

    wp.apiFetch({
        path: 'adf/v1/blocks/hero-block',
    }).then(data => {
        var templates = JSON.parse(data);

        templates.forEach((template) => {
            options.push({ value: template, label: template });
        });
    });