Tahdig

Tahdig is the crisp, golden crust that forms at the bottom of the rice pot, deliberately saved and served as its own course rather than mixed back into the fluffy rice above it. Every Persian rice dish produces some version of it, but tahdig is celebrated enough on its own that households and restaurants alike treat the crust as the meal's most contested piece, not just a byproduct.

What it really is

Partially cooked basmati rice, sometimes mixed with a little yogurt, saffron water or a thin layer of sliced potato or flatbread at the very bottom, packs into a hot, well-oiled pot. As the rice finishes steaming on low, gentle heat over a long stretch of time, the bottom layer, pressed against the hot pot, fries slowly into a crisp, deep golden crust while the rice above it stays light and separate. Once done, the pot inverts in one motion onto a serving plate, flipping the crust up and intact rather than breaking it apart inside the pot.

The successful flip is a real skill, and a broken tahdig is a genuine disappointment. Getting the whole golden crust to release in one piece, rather than shattering into fragments stuck to the pot, takes practice — a cook's tahdig technique is something regulars actually notice and comment on.

How it's served

• Flipped whole onto a plate, cut into wedges, served alongside the rest of the rice.
• As a side to any main Persian rice dish, sometimes ordered as its own item.
• Hot, straight from the pot, since it loses its crispness as it cools.

How to write it on the menu

• Flag the dairy if yogurt is used in the crust.
• It's naturally vegetarian.
• Say if it's made with a potato or bread layer at the base, since that changes the texture from the plain rice-crust version.