sudo dd if=path/to/iso of=/dev/<device> bs=1M status=progress conv=fsync
Note: <device> must be the device, not the partition, so /dev/sdc, not /dev/sdc2.
conv=fsync should force the progress report to show the actual buffered writes. Without this, the
progress report will show it completed, and then you'll wait for several seconds while the buffered
writes finish.
If for some reason your progress is not showing, you can check the size of the write buffer with:
cat /proc/meminfo | grep Dirty
You can run this several times and you should see the number slowly drop. Once it reaches about 100kB, your write should be finished.