Do you use a brisket that has already been corned? What is the best brand to use?
Yes, the brisket should be corned. I called around to butchers in my area and found that a lot had brined corned beef just for the holiday -- depending where you live, this could be a great option. The beef in the photo is from the Meat Hook in Brooklyn -- so good.
I also tried a version with Welshire Farms all natural corned beef from Whole Foods, which was delicious, but because it has no nitrates, the meat turns brown when cooked instead of staying the traditional pink.