Microwave 1/2 cut of butter until melted (approximately 1 minute.) Brush a 9"x13" ceramic dish with the melted butter.
Unroll fillo dough, lay flat on a cookie sheet, and cover with a washcloth to prevent it from drying out.
Place one sheet of dough into the pan, and brush with melted butter.
Fold fillo dough as necessary in order to make it fit in the pan.
Gently brush each layer with the melted butter. Continue to do this until you have used up half of the sheets.
Using a rubber spatula, spread the cooled custard over the fillo sheets.
Cover with the sheets, buttering each as you go.
Slice into squares, or diamonds, and pour any remaining butter over the top.
Bake for 30 minutes, or until golden brown.
Slowly pour syrup all over the pastry, making sure to distribute evenly. Allow to cool before slicing, and don't forget to share it with your friends!