In the mixer bowl, beat the butter with the sugar and salt. Add the egg and beat well.
Add the flour and baking powder, then slowly add the water, one tablespoon at a time, until the dough comes together.
Let it rest in the refrigerator for one hour or overnight.
On a floured work surface, roll out the dough as thinly as possible.
With the pizza wheel, cut the dough into strips, then cut in the other direction, to cut out the diamonds.

Refrigerate the dough pieces for 1 hour.
Heat the oil to 350F (180C), then fry the dough pieces until they are golden and crispy.
Dust with glazing sugar and enjoy!