Preparation / Directions:
Mix flours, salt, and butter and add just enough water to make a firm dough, somewhat like a biscuit dough. Knead for 10-15 minutes - the more the dough is kneaded, the lighter the bread will be. Shape the dough into a ball, cover with a sheet of plastic and let it rest for at least 1 hour. If left to rest overnight in the refrigerator, the finished bread will be even lighter.
When ready to bake, take a small piece of dough about the size of a golf ball, or a bit smaller. On a lightly floured board, roll the dough into a thin circle, about 5 inches in diameter. Repeat with all the dough. Heat a griddle or heavy-bottomed iron skillet until it is very hot (you will notice the smoke rising from it). Place the rolled out chapati on the griddle and let it cook for 2-3 minutes, depending on how thin you have rolled it. Using a pair of kitchen tongs, you can lift the chapati to see if the underside has turned a golden brown. Flip, and cook the other side about 1 minute.
As they are cooked, store the chapatis on a towel in a warm covered container until ready to serve. Serve as soon as the last chapati is baked.
NOTE: In India breads sometimes are baked in the fiery clay tandoor, where they develop brown spots and bubbles. To achieve a similar effect at home, you can use tongs to hold each chapati over a hot gas flame until it puffs like a little balloon. The chapati will collapse as it cools.