Add the chopped green chilies, chopped onions, chopped tomato, chopped curry leaves, wheat flour and salt in a bowl.
Add hot water and mix all of the ingredients well into a dough. The dough should be of spreadable by hand.
Heat a pan and spread 1/2 teaspoon of butter. Make an orange sized ball from the dough and spread on the pan using the tip of your fingers. If the dough sticks to your fingers, dip your fingers in water and then spread it.
Cook the appam on both side until slightly brown on low-medium flame.