Wash and soak chana dal in hot water for 10 mins. Later drain them.
Add rice flour, salt, jeera, chili powder, ginger, chili paste, curry leaves and soaked chana dal to a mixing bowl. Mix everything well.
In a small pot, bring 6 tbsps water to a boil and add butter to it. When the butter melts, pour the water and the melted butter to the rice flour.
The mixture will be hot so mix with a spoon first. Pour more hot to warm water and make a non sticky dough. Do not knead. Taste test and add more salt if needed. Cover the dough until used up.
Heat oil in a kadai on a medium flame. Meanwhile divide the dough to 14 to 15 portions and roll to balls.
Spread a clean and dry white cloth or a parchment paper. Place a ball and begin to flatten to a thin puri (as thin as possible). The dough begins to crack at the edges, just stick it up or dip your fingers in water and continue to spread.
Ensure chekkalu are thin and even. To prevent puffing prick them randomly with a fork.
To test if the oil is hot enough, drop a small flat piece of dough to the oil. It should sizzle and rise to the surface immediately without turning brown.
Gently remove the chekkalu one after the other and slide them to hot oil. Avoid touching for 2 mins. Fry them on a medium heat in batches of 3 to 4 depending on the size of your pan.
Turn them to the other side with a spider and fry until golden and crisp. When they are done bubbles will reduce. Remove to a steel colander or a cooling rack. Fry the rest in batches.
Cool chekkalu completely and transfer to a air tight jar. Discard the used oil.