In the pot heat up 3 tablespoons of oil, add the bay leaf, allspice, onion, leek and red cabbage. Stir and cook over a medium heat for 5 minutes stirring often.
Add the carrot, celeriac, potato, stock and balsamic vinegar, stir, cover and bring to the boil. Lower the heat and simmer for about 25 minutes (or until the vegetables are fully cooked) stirring occasionally.
Add the spinach, herbs, garlic, butter and season to taste. Add a splash of water/stock if needed. Cook for 2 more minutes. Remove from the heat and serve.
Red cabbage: Remove the tough middle, then chop the cabbage into 5 mm thick strips (or thinner).
Make it vegan: swap regular butter for vegan butter or margarine.
Spinach: For best results add it along with the herbs, crushed garlic and butter towards the end of cooking.
Herbs: Add your favourite combination of the recommended herbs.
Storing: Refrigerate leftover soup for up to 4 days.