1. Place the brisket or hump in a large pot and cover with water. Add the bay leaves and bring to a boil; then cook for one hour.
2. Preheat the oven to 160 degrees Celsius (320 degrees Fahrenheit).
3. Meanwhile, in a large pan, fry the onions in the oil until golden-brown. Add the sugar, ginger, garlic (if using), horseradish and wine, and leave to simmer for five minutes, allowing the sauce to reduce just a little. Mix in the tomato purée, peppercorns and jam until well incorporated.
4. Place the meat in a cooking bag and pour in the sauce. Slice the beetroot into quarters, then gently place them on either side of the meat in the cooking bag. Seal the bag with a wire tie and roast for four to five hours. Serve with a salad of your choice.