Just a regular breaker bar hooked up with a 1/2" drive Torx bit.
But, I forgot what size.
See attached.
Also, the part for the center
torx bolt is here.. Look for #12 in the picture.
That should help you to find the right size for the Torx bit.
WARNING:
Use the correct Torx bit or you will mess up the bolt and then it is a PIA to fix it.
Recommendations:
If you are planning to do stuffs on your Bimmer, go to HarborFreight and get a set of metric Torx bit. You will use them.