Methods

1. In a large bowl, combine the yogurt, biryani masala, and salt, and whisk until smooth. Add the chicken and stir to coat each piece in the marinade. Cover and refrigerate for at least 4 hours to overnight.
2. Place the basmati rice in a medium bowl, fill with cold water, swish the rice with your fingers, and drain. Repeat the process until the water almost runs clear, about 3 to 4 times. Fill the bowl with cold water and let the rice soak for 30 minutes to 1 hour.
3. While the rice is soaking, fry the onions. Heat ½” canola oil in karipot or 5-quart Dutch oven over medium high heat. Stir in half of sliced onions and cook, stirring occasionally, until deep golden brown, 9–12 minutes. (Keep an eye on the onions during the last few minutes, as they will darken quickly.) Using a slotted spoon, transfer onions to a paper-towel-lined plate to drain. Repeat the process with remaining sliced onions; set onions aside.
4. Discard the frying oil or save for another use and wipe out the pot. Return to the pot to medium high heat and add the ghee. Once the ghee is melted, add the marinated chicken and any leftover marinade, stirring to coat the chicken in the ghee. Cook, stirring occasionally, until the chicken starts to turn opaque and loses its raw appearance, about 6 to 8 minutes. Add ½ cup water, stir, scraping up any bits stuck to the bottom of the pan, cover, reduce the heat to medium low, and simmer, stirring occasionally, until the chicken is fully cooked through and tender, about 25 to 30 minutes. The chicken should release some liquid, but if the gravy starts looking dry, add a couple tablespoons of water during the cooking to loosen things up. 
5. Preheat the oven to 400°F.
6. While the chicken is cooking and the oven is preheating, parboil the rice. Bring a large pot of water to a boil over high heat. Salt the boiling water so it tastes like the sea (this is your chance to season the rice from the inside out!). Drain the soaked rice, add to the boiling water, stir, and cook until the grains are al dente, about 5 to 7 minutes. Drain and set aside.
7. Place the milk in a small bowl and heat in the microwave until hot, but not scalding, about 20 to 45 seconds (time will depend on the wattage of your microwave). Crumble the saffron into the hot milk and allow to steep for 10 minutes.
8. To layer the biryani, sprinkle the parboiled rice in an even layer over the hot chicken masala. Spoon the steeped saffron over the rice, then sprinkle with the fried onions and cilantro. Cover and bake until the rice is fully cooked through, about 25 to 30 minutes. Remove from the oven, keep covered, and allow to sit for 15 minutes before serving.
9. Serve directly out of the pot or transfer to a serving platter. Enjoy with more plain yogurt on the side.