Sift the flour, baking powder and salt in a large bowl.
Add the egg and soft butter, and start mixing with a spatula.
Add the cold water and mix well with your hands.
Work the dough on a slightly floured surface until well mixed. If necessary, add more flour or water depending on the consistency.
Divide the dough into small balls and let it rest for at least 20 minutes.
Using your hands or a rolling pin, extend the balls until very thin.
In a deep frying pan, heat the vegetable oil over medium-high heat.
Fry the yaniqueques until golden brown and rest over paper towel to absorb the oil.