Make a brine by combining 1 gallon of water, 1/4 cup of the pickling spices, 1 cup kosher salt, 3/4 cup light brown sugar and the garlic cloves(smashed) to a large pot. Bring it to a boil, then remove from the heat and let it cool completely.
Add the brisket to the brine, using a plate to keep it down under the surface. Refrigerate and allow to cure for two days.
Remove the brisket from the brine and rinse. Put the brisket in the crock pot and cover with water. Add the remaining 1/4 cup pickling spices and 1 can of light beer. Put the crockpot on high to bring to a boil then continue at a gentle simmer. Cover and cook for about 4 hours.
Add the potatoes, cabbage and carrots 20 minutes from the end of the time left to cook. Cook vegetable until fork tender, about 15-20 minutes.
Strain the meat and vegetables from the liquid. Slice the meat across the grain and serve on a platter with the vegetables. Sprinkle Maldon finishing salt, cracked black pepper, chopped cilantro and parsley. Serve with condiments of butter, dijon mustard and apple cider vinegar.