Redirect all outgoing DNS requests to the local Pi-hole instance using OPNsense

In my previous post, I had explained how I set up an N100 mini PC as an OPNsense firewall in my home network. One of the main purposes of having such a firewall was to (transparently) redirect all outgoing DNS requests to the local Pi-hole instance. I have a Pi-hole instance serving DHCP and DNS [ ]