[Alan Douglas]

As noted, a photo will help decide. Also knowing what tools you have available. You probably don't have a set of Forstner bits on hand, and the ones I've seen for sale recently aren't real Forstners, but have cutting teeth on the bottom edge. In any event the best way of aligning the break is to clamp the broken stub in place, and bore from the bottom all the way through the joint. Then you know the hole is aligned.

Quick-and-dirty is to drill holes in each direction and use an undersize dowel or steel rod, with epoxy to take up the misalignment.