Put beef in an appropriately sized pot, large enough to hold the piece of brisket with a little room to spare. Cover with one can each of the beer and the ginger ale. We’ve suggested 2 cans of each. Use the additional cans if you need more liquid. Keep any spares and add during the cooking process. If you run low of the beer and ale, during cooking, supplement with water. Add all other ingredients, 4 carrots if following the alternative, except cabbage and bring to a boil with the lid off the pot. Turn to simmer and cook for 3 hours. Skim fat from top as it rises.
With 20 minutes to go -
Remove the thyme, parsley and onion. Add cabbage. Simmer for 20 minutes until cabbage is cooked
Turn oven to 400º degrees. Place top shelf of the oven to the highest position.
Do not add the cabbage to the pot with the beef. Separate cabbage leaves, drizzle with olive oil, salt and paper. Clean and cut the leaves off the the remaining 6 carrots, cut into appropriate roasting size
Roast carrots and cabbage on a sheet pan, until nicely cooked. Check for doneness after 20 minutes. If needed, keep roasting until finished. Remove carrots. Switch to broil. Broil cabbage for a few minutes to crisp the edges. Depending on your flavor desires
Remove the meat and cut into pieces. Place on center of a large platter. Strain the cabbage and season it heavily with black pepper. Surround the beef with the cabbage, carrots and potatoes. Serve with horseradish sauce.
Horseradish Sauce
1/2 cup mayonaise
2 to 3 tablespoons prepared horseradish
Splash of lemon juice
Salt and pepper to taste
Mix ingredients and place in the refrigerator until ready to eat.