1) In a small food processor (mini-chopper), combine the garlic, ginger, and 1 tablespoon water and puree to a paste.
2) Heat the oil in a stew pot over medium-high heat. Add the coriander, cumin, cardamom, allspice, cloves, cinnamon stick, and bay leaf and cook, stirring constantly, until toasted and fragrant and the cinnamon stick unfurls, about 30 seconds. Add the onion and cook, stirring, until lightly browned, about 3 minutes. Add the garlic-ginger paste, curry powder, and jalapeno and cook, stirring, until lightly browned and fragrant, about 1 minute.
3) Add the tomato and cook, stirring, until the oil begins to separate and there is a distinctive crackling sound as the ingredients "re-fry" in the oil, about 6 minutes.
4) Add the vegetables, season with salt and pepper and stir to combine.
5) Add the coconut milk and enough water to just cover the vegetables. Bring to the boil, lower the heat, and simmer, covered, until tender, about 15 to 20 minutes.
6) Using a slotted spoon transfer the vegetables to a bowl. Bring the to the boil and cook, stirring occasionally, until reduced to a sauce-like consistency.
7) If using the chicken, add and reheat. Return the vegetables to the sauce and stir to combine. Season with salt and pepper. Transfer to a platter and garnish with the coriander.