Yes you can cook Kala Chana without soaking it overnight. To cook Kala Chana without soaking, you need to add a pinch of Meetha Soda (Baking Soda) while pressure cooking it. If you add too much Baking Soda, you may find slight difference in taste. Mostly this taste difference is very minor and easily go un-noticed. Adding Baking Soda can save you time and help lower your energy bill if you care planning to make it quite regularly.