I thought I had melted chocolate (Nestle morsels) in the microwave
on medium-low setting before, stirring often, but something really
went wrong last time I tried this: It turned into what looks like a
brick of cocoa.

It's crumbly and looks dry. But it tastes fine - Heck maybe even
better tasting then when it was in morsel form. Has a nice crumbly
texture, not smooth, but it smooths out in the mouth. Not really
dry at all, not as dry as it looks. When it happened I just let it
cool and stuck it all in all in a plastic bag and tried to forget
about it... until now.

What did the microwave do to it? And is there a way to bring this
back to a smooth melted consistency for dipping? (for my lace
cookies).

-sw