What is the default genesis.json file for Besu?

I am running Besu (besu --config-file=besu.conf ) with the following config file:

data-path="./besudata" #genesis-file="./genesis.json" rpc-http-enabled=true rpc-http-host="127.0.0.1" rpc-http-port=8545 rpc-http-api=["ETH","NET","WEB3","CLIQUE"] rpc-http-cors-origins=["all"] host-allowlist=["*"] network="dev" miner-enabled=true miner-coinbase="0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266" min-gas-price=0 

A single node private network is what I am aiming for here as my starting point. This is working fine. I have a local node that is mining transactions and I can connect to the JSON RPC.

I would like some control over the genesis file now.

I have tried using the genesis file here:

https://besu.hyperledger.org/23.4.0/private-networks/how-to/configure/consensus/clique

This isn't working, mining has stopped. What do I need to fix here? Initially I just want exactly the behaviour I am getting as a default out of Besu for this test scenario.