Consider this a template recipe for making Turkish burek, which come in all shape and filling combinations. Use high-starch russet potatoes for a creamy mash, and, if you can find it, young kasseri cheese (you can substitute with 1 1/2 cups grated emmentaler and 1/2 cup grated pecorino). The flatbread these burek are wrapped in is called yufka, which is thicker than phyllo but thinner than a flour tortilla. Look for them in specialty import shops or online. The triangular ones sheets, about 30 to a pound, are perfect for sigara burek. If you can't find yufka, use three sheets of phyllo with clarified butter brushed between the layers.