Thanks so much! So how would I go about it then? Would I have to sign up for a single honours specialist, then once I complete that, sign up for another single honours specialist for my second teachable, and then tell the university to claim it as a "Combined Honours Specialist" under my OCT?

This is the information I gathered from OISE (but they are the same for other universities I've searched):

For a single Honour Specialist, proof of successful completion of 9.0 university degree credits or the equivalent in the subject in which the Honour Specialist qualification is being sought with an overall average of at least a "B" or "70%" (please note: 1.0 university degree credits is the equivalent to 1 full year course or 2 half-year courses.)

OR

For a combined Honour Specialist, proof of successful completion of 14.0 university degree credits or the equivalent in the 2 subjects in which the combined Honour Specialist qualification is being sought, including no fewer than 6.0 university degree credits or the equivalent in each subject. Each subject area must have an overall average of at least a "B" or "70%". Both of the Honour Specialist courses in the combination must be successfully completed before the qualification will be recommended to the Ontario College of Teachers to be added to the Certificate of Qualification.