1. Place Jerusalem artichokes and potatoes in a large pot of salted water; bring to a boil over medium-high heat. Reduce heat to low and simmer until tender, about 10 minutes. Drain and set aside.

2. Place lamb in a large pot and cover with water; bring to a boil over medium-high heat. Reduce heat to low and simmer for 2 minutes. Remove from heat and drain.

3. Transfer lamb to a large pot along with onions, carrots, bay leaves, vinegar, peppercorns, mustard seeds, coriander, and 16 cups water. Bring to a simmer over medium heat and cook for 1 1/2 hours, skimming foam from the surface as necessary.

4. Stir in reserved Jerusalem artichokes and potatoes, honey, ketjap manis, mustard, and cream; bring to a boil. Reduce heat and simmer for 10 minutes. Remove bay leaves and discard. Stir in dill and season with salt.