Forget ezy-outs- if stud is broken off flush because it's jammed or rusted, you have a 50/50 chance of breaking the ezy-out in there, and they are hardened so you just made the job a lot `harder' (pun intended).
On bolts or studs that are flush, I drill them on centre to the tapping drill size and screw the right size tap in. When you undo the tap it winds the remains of the stud out.
Pretty easy job on Minis as everything is cast iron, outboard motors (alloy and S/S bolts) are trickier, that's where I learned to do it properly.
