can i restore using custom firmware that pwnage.app made to jb my phone?

I have jb my phone before with pwnage, but had to restore back to factory firmware... and I still have the custom.ipsw file that pwnage made for me. Now i was curious can i just use itunes and restore using that custom ipsw to jb my phone or do I have to go to the entire pwnage process again?

I tried doing this but after the restore process using the custom.ipsw i dont see cydia on my home screen at all... sigh... somebody please help...