Kirby index field - customise date

I’m using the Kirby-Index-Field plugin and it’s great, however, I need to format the dates in one of the columns. It’s currently outputting 2018-07-26T13:01:45+00:00 ideally, I need something like 26-07-2018. The description says you can do this through a filter, but I’m not sure how to use the template code given. Any pointers in the right direction would be appreciated.

<?php

class MyDataFilters {
  static function myfilterfunc($data) {
    // filter data here
    return $data;
  }
}

@jongacnik, could you help with this, please?