Place 1 sheet of phyllo dough on a cutting board. Brush with some of the butter and sprinkle with some of the sugar. Cover with another layer of phyllo dough and repeat until there is a total of 3 layers. Cut into 7.5-cm / 3-in squares.
Line a half sheet pan with a nonstick rubber mat. Place the phyllo squares on the mat and bake until golden brown, about 7 minutes.
Once cooled, reserve in an airtight container at room temperature. Discard after 2 days.