I made a pizza today for lunch, and when I looked for a package of
mozzarella, there was an unopened package that didn't match -- it had
been in there for a year and got shuffled to the back of the fridge and
somehow made it back to the front. I looked it over and there was no
mold so I used it.

As I was grating it, it felt firmer and less rubbery than it should, so
I tasted a piece. It was strong, with a flavor and texture kind of like
sharp cheddar. So I put it back and got one of the fresh packages and
used it (but I left the roughly 1 ounce of the old sharp cheese on the
pizza)

The sharp cheese messed up the flavor of the pizza but didn't ruin it,
but that's not really the point. Has anyone eaten aged mozzarella
before? I think I've heard of aged provolone cheese; maybe that's what
I inadvertently made by aging the mozz.

-Bob