Heat the oil in a saucepan and sauté the ginger till soft. Add the water and bring it to boil then add the sugar and black peppercorns. Once the sugar dissolves, add the oyster sauce followed by the vinegar, cumin seeds and curry leaves and cook till thick.
Dust the calamari in cornflour and paprika powder and fry on a high heat to get a crispy texture. Place it on a kitchen towel.
Heat the sauce in a wok on high heat and stir fry the calamari and add the coriander leaves. Serve hot on a plate and sprinkle chat masala and curry leaves on top.