Put the corn and milk in a heavy pan. Bring to a simmer, making sure it doesn't boil over. Simmer vigorously, stirring occasionally, until there is very little milk left (just enough to keep the corn looking wet).
Heat the oil in a frying pan over medium heat. When hot, put in the cumin seed. A few seconds later, add the ginger and green chili. Stir once.
Add the corn, sugar, salt, and cayenne to the frying pan. Stir to mix. Add the coconut and cilantro.