Mix the flour and coconut milk to make a dippable semi thick batter. Beat the eggs separately, add to the batter and mix well. Lastly add the cumin seeds, salt and sugar combine well. Keep aside for half an hour.
Heat the oil in a deep bottomed vessel. Dip the achappam mould in the hot oil.
When the mould has heated up, remove it, shake off the excess oil and dip 3/4th of the mould in the batter. Ensure to dip only 3/4th of the mould in the batter, otherwise, the achappam cannot be unmoulded properly.
Now take the mould from the batter and dip it in hot oil. When the batter is cooked, it will start detaching itself from the mould. If you have problems in unmoulding, use a fork to gently unmould.
Repeat the process for the rest of the batter. Store these achappams in an airtight container after they cool down.