Adding additional network to site-to-site VPN

I have a IPSec site-to-site VPN setup between a Ubiquiti EdgeRouter and a Sonicwall. I would like to add another network to the list of allowed traffic.

For example, currently on the edgerouter side I am passing 192.168.1.0 network over the VPN, I would like to add a VLAN network 192.168.2.0 to the list to allowed traffic. Do i need to create a completely new tunnel or can I easily add it to the existing tunnel.

Thanks