Openwrt selfmade direct to a sdcard?

Can I build OpenWrt to an image that I can transfer directly to a sdcard?

my workflow right now is:
$ make menuconfig
$ make
Install new .img by USB Drive connected to the board.
then copy to /overlay on sdcard like this:

mkfs.ext4 /dev/mmcblk0p1 
mount /dev/mmcblk0p1 /mnt 
tar -C /overlay -cvf - . | tar -C /mnt -xf - 
umount /mnt
block detect > /etc/config/fstab
vi /etc/config/fstab

then install packages with pip

That takes quite long to find out if my menuconfig works properly...
Is it possible to shorten that by creating an image that I can burn to the sdcard directly like I do with a Raspbian on a Raspberry Pi with `Balena Eatcher? or so?