Mix together the egg, sugar, milk, butter and baking powder. Slowly mix in the flour, forming dough that’s soft but not sticky. Add more flour if needed.
With a rolling pin, roll the dough on a lightly floured surface until it's about ¼-inch thick. Let it stand about 20 minutes, then cut it into 12-15 triangles.
Heat the oil in a skillet. Place the triangles in oil over medium heat and fry until both sides are golden brown. Remove to drain on paper towels. Sprinkle with powdered sugar.