Start by rinsing the lentils under cold water until the water runs clear. If you have time, soak them in water for about 30 minutes to help them cook faster.
In a large pot, bring 3 cups of the vegetable broth or water to a boil. Add the rinsed lentils and 1 teaspoon of salt. Reduce the heat to a simmer and cook for about 20-25 minutes, or until the lentils are tender but not mushy. Drain and set aside.
In the same pot, add the remaining vegetable broth or water and bring it to a boil. Stir in the basmati rice and the remaining salt. Once it boils again, reduce the heat to low, cover, and let it simmer for about 15 minutes, or until the rice is fluffy and the liquid is absorbed.
While the rice is cooking, heat 2 tablespoons of olive oil in a frying pan over medium heat. Add the coriander and cumin seeds, cooking for about 1-2 minutes until fragrant. Then, add the allspice, cinnamon, turmeric, and black pepper, stirring to combine.
In a separate bowl, toss the sliced onions with the flour until they are lightly coated. In the same frying pan, add the vegetable oil and heat it. Once hot, add the prepared onions and cook, stirring frequently, until they are golden brown and caramelized, about 15-20 minutes.
Once the rice and lentils are cooked, gently fold them together in the large pot. Add the spiced oil mixture and half of the caramelized onions, stirring to combine evenly.
Spoon the Mujadara onto a serving platter and top with the remaining caramelized onions. Garnish with fresh chopped cilantro and lemon wedges for a burst of flavor. Enjoy your Mujadara warm!