In a medium cast iron skillet over medium heat, add the chilis, cinnamon sticks, bay leaves, peppercorns, mustard seed and cloves. Toast just until they become fragrant, stirring occasionally, about 3 to 4 minutes.
Remove the spices and crush finely with a rolling pin.
For the brine: In a large mixing bowl whisk together the the beer, brown sugar, pickling salt, kosher salt, coriander powder, allspice, ginger and water.
Whisk in the toasted spices, all but ⅓ cup which will be reserved for later.
Pour half the brine mixture into a large casserole dish. Add the brisket and pour the remaining brine mixture over top. Cover and place in the icebox for 5 days. Flip the meat over once a day and stir the brine solution.
Remove the brisket from the icebox and rinse with water.
Fill a large stock pot half full with water and bring to a simmer over medium-high heat. Add the table salt and the reserved toasted spices. Add the brisket to the pot. Be sure that there is enough water to cover the brisket by about 3 inches.
Cover and simmer over medium heat for 2 hours. Remove and place in a large Dutch oven or casserole dish. Add the beef broth, cabbage and potatoes. Cover and bake at 375 degrees F. for about 2 hours, or until fork tender.
Remove the brisket and let cool slightly. Cut against the grain. Serve hot with cabbage and potatoes.