Fatayer (فطاير) are small filled dough pastries, folded into triangles or pinched into open boats around a savory filling and baked, the Lebanese hand pie that functions as a portable sandwich in everything but name. The angle is the seal. A fatayer is a self-contained bread parcel, so it stands or falls on the relationship between a thin, tender dough and a filling that has been managed for moisture. Too wet a filling and the dough goes soggy or splits in the oven and weeps; too dry a filling and the pastry eats like plain bread with a smear inside. Get the dough thin and the filling balanced and it is a clean, two-bite package of crust and savory interior. Get it wrong and it is either a leaking mess or a bready, underfilled disappointment.
The build is dough plus filling plus a fold that has to hold. The dough is a soft, lightly enriched bread dough, sometimes with olive oil and a little yogurt or milk, rested so it rolls thin without tearing. It is cut into rounds, the filling spooned into the center, and then closed: the classic spinach version is pulled into a three-cornered pyramid with the seams pinched tight so steam cannot force them open, while cheese and meat fillings are often left as open boats or half-moon turnovers. The closed shapes are the test, since a seam that is not pinched firmly will burst and spill in the heat. They are brushed with oil or egg and baked until the dough is set and lightly colored, kept short of hard so the shell stays tender. A good fatayer shows a thin, even crust with a defined fold, a filling that is moist but contained, and no grease pooled under it. A sloppy one is thick-walled and underfilled, or split along a seam with the filling baked dry and dark at the breach.
It varies first and most by the filling. Spinach with onion, sumac, and lemon is the archetypal closed triangle; cheese, usually akkawi or a mix, and spiced ground lamb or beef are the other two pillars, each typically given its own shape. Beyond those, kitchens fill them with za'atar, labneh, potato, or seasoned greens, and the format itself shifts between the small folded pastry and a larger open-faced flatbread closer to a manoushe or sfeeha. Each of those, the cheese version, the meat version, the larger open rounds, is a recognizable form in its own right and deserves its own treatment rather than a footnote here. They all return to the same idea: a thin dough sealed around a managed filling and baked, judged on whether the parcel held.