Makes about 15 slabs of fried dough the size of a small plate
Mix together the flour, baking powder, and salt.
Cut the cold butter into bits and work it gently into the dough.
Add the water and stir until the dough is all combined.
Cover the dough with plastic wrap or a damp towel and let it rest for 15 minutes
Separate the dough into pieces and flatten each piece into a thin disk with your fingers. If it's sticky, put a little confectioner's sugar on your work surface.
Heat the oil in a pan. You can deep fry it or use less oil and fry it in a small amount of oil; your choice. The oil is ready when you put a wooden spoon in and little bubbles form around it.
Carefully lay the disc of dough in the hot oil. Let it cook a few minutes, just barely getting brown, and then turn it and cook the other side.
Remove the dough, let the excess oil drain off, and sprinkle it immediately with sugar and cinnamon if you like.
You can keep these hot in the oven for a bit, but they're best when they're very hot.