1. For Vegans ,you can skip yogurt and add lime juice.
2. If you are using canned chickpea ,you can add directly ,or else soak chickpea for 5-6 hours or overnight and pressure cook for 3-4 whistles.Alternately you can boil soaked chickpea in a pan as well
3.You can get chole masala powder and biryani masala powder from any indian grocery store.You can use any brands.
4. Since tomato-onion mixture releases water ,hence i reduced 1/2 cup of water,ie i added 2.5 cups of water for 1.5 cups of rice.
5. You can also do a Natural Pressure Release(NPR) ie wait for 10 minutes after the POT beeps and then open the lid.
6. You can increase or decrease spice accordingly.
7. You can add fried onions on top before serving.