Shred the coconut into a clean cloth. Fold the cloth around the shredded coconut. Wet the cloth using a glass of warm water. Squeeze the cloth and the shredded coconut to extract the coconut milk. Discard the shredded coconut.
If obtaining and shredding a fresh coconut is not possible, you may substitute a can of unsweetened coconut milk instead.
Add a small amount of oil to a frypan.
Saute chicken until done over medium heat.
Add onions to pan. Continue stirring over medium heat until the onions are brown.
Add ginger, tomatoes and garlic to the pan. Saute together briefly over medium heat.