Place one sheet of thawed Fillo dough on a greased cookie sheet. Spray dough with cooking spray. Place another sheet of dough on top. Continue with this pattern until you have 6 sheets of dough. Do not spray the top sheet. Cut into 8 squares with pizza cutter. (My sheets were 9" 14", so my "squares" were actually rectangles and measured about 3.4"x4.5" each.) Press each square into a muffin pan cup. Make 24 pastry cups with this method, then bake them for 9-12 minutes or until light golden brown. Do not overbake because they will go back in the oven once they are filled.