In a heavy, dry skillet over moderate heat, toast the coriander, cumin, and fennel seeds, stirring, until fragrant and a shade or two darker, 3 to 5 minutes. Be careful not to burn them.

Preheat the oven to 400F / 200 C

Place the toasted seeds, diced tomatoes, ginger, garlic, chilli flakes, sambal chilli, and brown sugar in an oven-proof dish. Mix to combine and roast in the oven uncovered for 30-40 minutes. Set aside and allow them to cool completely.

Process the roasted tomato mixture in a blender or food processor till smooth. Pour the tomatoes into a pot. Add the chicken/vegetable stock. Bring the soup to a boil and simmer on medium heat for 25 minutes.

Top the soup with a dollop of Greek yogurt and some chopped Italian parsley, cilantro, or chives.

SERVES 4