Disconnect the power cord from the Mac Mini. Plug USB-C/Thunderbolt cable into the USB-C port next to the ethernet port. Plug the other end into the Host Mac. While holding down the power button, connect the Mac Mini to power and continue to hold the power button for about 3-5 seconds You should now see the DFU logo on the Host Mac.
I recently purchased one of the newer Mac mini devices with the new M1 chipset. Unfortunately I went with the lower edition that had 256 GB and I wanted to send it back to purchase the bigger 512 GB edition, but I wanted to clean my installation. In order to to boot in the recovery mode to reinstall the os I had to perform the following steps: Make sure the Mac mini is off, if its not off just shut it off Hold the power button until the options appear, it might seem like a long time but keep holding it. It took about 15 seconds for me. A menu should appear that shows the hard drive and Options. Select options and continue You will see the apple logo and then a new menu should appear with additional options. It would look like this: ...