Laminated dough

Laminated dough is a culinary preparation consisting of many thin layers of dough separated by butter, produced by repeated folding and rolling. Such doughs may contain over eighty layers. During baking, water in the butter vaporizes and expands, causing the dough to puff up and separate, while the lipids in the butter essentially fry the dough, resulting in a light, flaky product. Examples of laminated doughs include:

...
Wikipedia