So I decided to attempt to migrate from ISC DHCP v4 to Kea DHCP but when I was setting things up in Kea, I don't see anywhere to set your DNS server. I have a custom pi-hole DNS server at a static IP on my network and I want that for my DHCP clients. But even though the docs say there's a field to set DNS, I don't see it anywhere in Kea.
Kea -> Subnets -> <your subnet> -> Uncheck "Auto collect option data"
Edit: Sorry, I was too hasty in submitting this without an explanation. I noticed that if you uncheck that option, then additional options open up where you can specify the DNS.