In a deep skillet, or shallow pot, heat the oil on medium heat.
Add in the onions. Cook, stirring often, until the onions are a deep golden brown, about ten minutes. The deeper the colour, the darker the masala.
Add the garlic, ginger, green chilis, cardamom, cloves and cinnamon. Cook until fragrant, about two minutes.
Add in the cubed lamb, cook stirring often for fifteen minutes. This step is important as it helps remove the gamey taste from the meat, and gives the lamb a nice browning that adds a deep flavour to the dish.
Add the ground coriander, stir to combine and cook for one minute.
Add in the turmeric, cayenne pepper, nutmeg, cumin and mace. Mix well and cook for another two minutes.
Add in a third of a cup of water, mix well and bring to a simmer for two to three minutes.
Add the yogurt, tomatoes and salt. Stir to combine and bring to a simmer.
Cover the pot or skillet with a lid and cook the lamb masala on medium heat, stirring every ten minutes, for about forty five minutes, or until the lamb is just reaching fork tender. The lamb will be cooked slightly longer in the oven, I like to cook it until I'm able to break the lamb between two fingers, with light pressure. The curry of the lamb will be thick, not runny, similar to biryani. It will be layered between the rice so we want to be sure the masala is on the thicker side but not completely dry. If need be, add in a quarter cup of water during cooking time to loosen up the masala in case it dries up too much.
While the lamb is cooking, make the rice.
After soaking the rice, strain it well and then add it to a pot with 1 3/4 cups of fresh water.
To a deep skillet, add another 1 3/4 cups of water and the bay leaves. Bring to a boil on high heat.
Add the oil, pinch of saffron, salt and rice along with the water it was in.
Leave the skillet uncovered, on medium heat, and cook the rice until the water is absorbed. The rice will be almost cooked, but have a bite to it. Do not over cook the rice!
Preheat your oven to 325F.
Combine the rose water and crushed saffron in a small bowl, set aside.
Once the lamb is about 95% cooked, add in the lemon juice and cilantro. Stir to combine.
Grease a deep 9x13 baking dish with neutral oil. Spread half the rice over the bottom of the dish. Spoon over the lamb korma, spreading it evenly over the rice. Sprinkle a generous amount of chopped cilantro and mint over the lamb and finish off with the remaining rice.
Use foil or an ovenproof lid to cover the baking dish tightly. Place in the oven and bake for 15-20 minutes, or until the rice is fully cooked.
Garnish with cilantro and lemon slices. Serve in the baking dish for a beautiful layered presentation, or spoon out into a serving dish and serve immediately.