Tachin

Often credited to southern Iran (Shiraz, Fars province), though its origin is disputed — Persian and encyclopedic sources also trace it to Semnan/Garmsar (the Garmsari variant) and to the molded-rice traditions of Tabriz in the Azeri-Persian northwest, dating in its current baked-cake form to at least the Qajar era (1789–1925). The pre-Islamic Persian origin is rice-and-yogurt scorched-bottom cookery, which the Safavid court refined into formal polo technique. Tachin is the only major Persian rice dish baked in the oven rather than steamed in a pot — the rest of Iran's polo tradition is stovetop.

Shiraz and Fars specialty, codified into baked-cake form during the Qajar era (1789-1925) — the only major Persian rice dish baked rather than steamed. Yogurt and egg yolks bind parboiled rice into a sliceable wedge during a 75-minute oven bake. Low-fat yogurt breaks and weeps; full-fat strained Greek-style is required.

A baked rice cake — saffron-and-yogurt rice pressed into a pan with shredded chicken layered through the middle, then oven-baked until the bottom turns into a single sheet of deep-golden tahdig. Inverted onto a platter, sliced like a cake. The contrast you want is the crackling base against the saffron-soft interior; barberries scattered on top supply the sour cut.

Yogurt and egg yolks are whisked with bloomed saffron, then folded into parboiled rice — the proteins coagulate during baking and weld the rice into a sliceable cake. The yogurt must be full-fat strained (Greek-style); low-fat versions break and weep, and the rice cake collapses when inverted. Bake at 350°F (180°C) for at least 75 minutes uncovered to let the bottom crust form.