Hello! I was wondering whether anyone has tried these with another cheese, such as parmesan? I've got a whole bunch of parmesan sitting in my frid...

Sounds good! Save all your parmesan rinds and you can use them to enrich your soup stock. They can be frozen.

haven't tried it but see no problem. when substituting one cheese for another, you'll obviously get different (good) tastes. Keep in mind that you'll get better results subbing by texture - a hard cheese (like Parm) for a hard cheese (like cheddar). Not hard for soft or vice versa.