Tahchin-e Zereshk va Gerdoo (ته چین زرشک و گردو) — Persian Saffron Rice Cake with Barberries and Walnuts

• 500 gBasmati rice (rinsed until water runs mostly clear)
• 3000 mlWater (for parboiling rice)
• 18 gSalt (divided, plus more for boiling water if needed)
• 300 gPlain full-fat yogurt (unsweetened)
• 4 largeEgg yolks (about 72 g yolks total)
• 1 largeEgg (about 50 g without shell)
• 0.5 tspSaffron threads (about 0.2 g)
• 45 mlHot water (to bloom saffron)
• 90 mlVegetable oil (divided, plus extra to grease the pan)
• 450 gGround lamb (15–20% fat preferred)
• 250 gOnion (finely diced)
• 1 tspBlack pepper (freshly ground)
• 80 gBarberries (rinsed and drained well)
• 90 gWalnuts (coarsely chopped)

Instructions

1. 1

   Rinse the basmati rice in several changes of cold water until mostly clear. Soak the rice in plenty of cool water with 10 g of the measured salt for 30 minutes, then drain. Meanwhile, preheat the oven to 190°C (375°F) and place a rack in the middle.

2. 2

   Bring 3000 ml water to a rolling boil in a large pot. Add the drained rice and boil 6–8 minutes, stirring once or twice, until the grains are tender on the outside but still firm in the center. Drain immediately and rinse briefly with cool water to stop cooking; drain very well.

3. 3

   Bloom the saffron: crush the saffron threads with the back of a spoon, then stir into 45 ml hot water and rest 10 minutes. In a large bowl, whisk yogurt, egg yolks, whole egg, the remaining 8 g salt, and saffron water until smooth. Whisk in 90 ml oil until fully emulsified.

4. 4

   Cook the lamb filling: heat 15 ml oil in a skillet over medium-high heat. Add diced onion and sauté 6–8 minutes until golden. Add ground lamb, 4 g salt, and black pepper; cook 8–10 minutes, breaking it up, until browned and no pink remains. Cool 10 minutes so it does not overcook the eggs later.

5. 5

   Prepare the barberry-walnut layer: in the same skillet over medium heat, warm 10 ml oil. Add drained barberries and stir 45–60 seconds just until glossy and fragrant; do not let them burn. Remove from heat and toss with chopped walnuts so the nuts pick up the barberry tang.

6. 6

   Combine rice and binder: add the well-drained parboiled rice to the saffron-yogurt mixture. Fold gently with a spatula for 1–2 minutes until every grain is coated and the mixture looks uniformly yellow. If the rice feels wet, rest 5 minutes so excess moisture is absorbed.

7. 7

   Assemble for a crisp crust: generously oil a 23–24 cm (9–9.5 in) round cake pan or springform pan, including the sides. Press half the saffron rice firmly into the base and up the sides by 2–3 cm. Spread the lamb evenly, then scatter the barberry-walnut mixture over the lamb.

8. 8

   Top and bake: cover with the remaining saffron rice and press firmly to compact. Cover tightly with foil and bake 45 minutes at 190°C (375°F). Remove foil, reduce to 175°C (350°F), and bake 20–25 minutes more until the edges are deep golden and the top feels set.

9. 9

   Rest and unmold cleanly: cool the tahchin 15 minutes in the pan so the crust releases without tearing. Run a thin knife around the edge. Invert onto a serving platter, tapping gently to release. Slice with a sharp knife; serve warm so the lamb stays juicy and the crust stays crisp.