Take 500 grams mutton (cut into small pieces) in a bowl and marinate them with 1 tbsp of ginger garlic paste and salt to taste. Keep it aside overnight. You will need pressure cook this the next day with water for up to 5 to 6 whistles until the mutton is nice and tender.
In another bowl, take 300 grams each of split pigeon pea (Toor dal), split brown lentils (masoor dal, split or unsplit, with skin or without skin), split green gram (moong dal), split Bengal gram (chana dal) along with 100 grams broken wheat (Dalia). Wash them all nicely with water at least with 2 to 3 changes of water until the water becomes clear. Then soak them individually or all together for at least 2 to 3 hours before pressure cooking them for up to 3 to 4 whistles until they become mushy.
Heat 2 tbsp of cooking oil to fry 1 cup finely chopped onions. Remove them when they turn to nice brown color and keep them in a bowl aside.
Heat a wok on a high flame and pour 2 tbsp of cooking oil in it. As it heats up, put in ¾ cup of fried onions, 1 tbsp of red chili powder, ½ tsp of turmeric powder, 1 tbsp of coriander powder, 1 tsp of garam masala powder, and 1 tbsp of whole spices consisting of an inch-sized cinnamon stick, 1 piece of mace, 4 green cardamom pods, 4 cloves, and 2 pieces of whole bay leaves. Now mix all of this together and turn the flame to low. Mix and let them cook on a low flame for about a couple of minutes.
When ready, add the boiled lentils. Mix them with the masala. Also, add the boiled mutton to it. Mix all of them slowly and nicely. Let it cook for around 10 minutes on an absolutely low flame.
When the oil comes on the surface, turn off the flame and transfer it to a serving bowl.
Your tasty and spicy homemade mutton khichdi is now ready to enjoy. Serve it hot after topping it up with the rest of the fried onions, lemon juice, along with a few freshly chopped coriander and mint leaves.