Thanks! Yes it made plenty...
It looked like maybe originally 6 cups? I'm not good at eyeballing these things in the pan. I did make a full batch to be sure I'd have enough, but I think this icing might be a bit above my pay grade.
I was unprepared for how thin it was, though the word "glaze" shoudda tipped me off. Also, didn't realize as it cools it stiffens up. A lot. So added more sugar to thicken since I was going to pipe. Then as I let it cool enough so I could work with it, it started to harden, to the point I had to prop the mixer on the edge of the pan and leave it on because in seconds it would harden, but it was still runny.
At this point I knew I'd created some other life form.
I thinned it out and mostly all was well (though I never found the magic texture to pipe that wasn't a bit stiff or too runny), but it was interesting in that it seems to harden from the bottom up. I took some out to color and when I went back to it, the bottom turned into what reminded me of molding clay - I'd never seen icing take on this texture. I couldn't scrape the bottom with my spoonula, had to use metal, and it nearly bent, but the top was still runny. Maybe I cooked it too long or not enough. Basically I had it on med heat and mixed till well combined/looked like a glaze and called it done.
I did so much doctoring in the way of adding more sugar to thicken, and then water to thin it, then a bit more corn syrup b/c I'd used a scant 1/3 cup following Penny's tip to harden faster, not sure I can review for taste. Also, I subbed almond extract for vanilla, because that's how I roll with sugar cookies. (I used my cookie recipe.) I have a *lot* leftover. (Anyone need neon green and blue Toy Story colored icing?)
It was a very interesting experiment though and I'm glad I tried it because I learned a lot. Screw-ups at least give you that. One thing to note, in going over the additional tips Lisa posted, Penny said she used this as a base glaze, and then used Royal Icing to decorate. Humm.
They're done and I'm hoping they'll dry ok. Since getting it too stiff (actually it was never stiff, it would just harden instantly - the drips off the beaters hardened like a frozen waterfall at one point) and then watering it down a few times, the cookies 4 hrs later are set though aren't dry like royal would be, but the stuff in the pan at one point seemed like it would turn rock hard.