Date formatting and binding

Hi Everyone,

I have an API which returns open slots in a calendar on a specific date, like below:

[{"st":"2020-07-21T09:00:00"},{"st":"2020-07-21T09:30:00"},{"st":"2020-07-21T10:00:00"}]

I would like to display this data in a select field, like below:

Any idea on how to configure the server connect action in order to return list with the available times formated. So far this is what I have and the formatting is not working, and when I try to bind with the select field, it is displaying undefined.