For the Pickling Spice: Combine all into a small bowl.
For the Brine: In a medium saucepan, boil the water with the spices, salt and sugar, reserving 1 tablespoon of Pickling Spice. Once the water boils, remove from heat and cool to room temperature.
Meanwhile, place the brisket in a large container and pour the cooled brine over it, being sure it is fully submerged. Refrigerate, covered, for 6-7 days.
To Cook the Corned Beef: Remove the brisket and rinse in cool water. Place brined brisket in a large pot with reserved Pickling Spice and cover with 1 inch of water. Simmer for 4-5 hours, covered, until fork tender.
For the Caraway Cabbage: In a medium sauté pan, heat butter and oil over medium heat. Add onion and sauté until translucent, about 3-4 minutes. Add the caraway to the pan and cook for another 2 minutes.
Add 1/2 of sliced cabbage and mix well. Allow the mixture to sit a few minutes without stirring so the bottom lightly browns.
Add remaining cabbage and mix well. Allow bottom to brown once again. Deglaze the pan with Guinness and cook until stout is reduced. Season with salt and pepper to taste.