Season the barramundi with some salt and pepper, and make sure they are as evenly coated as possible. Sprinkle half of the Cajun seasoning onto the fish and give it a stir- make sure it is coated well and set aside.

Put the ghee in the Instant Pot and push “Sauté”. Wait until it reads “Hot” and add the barramundi chunks. Sauté for about 4 minutes, until it looks cooked on both sides. Use a slotted spoon to transfer the fish to a large plate.

Add the onions, pepper, celery and the rest of the Cajun seasoning to the pot and sauté for 2 minutes until fragrant. Push “Keep Warm/Cancel”. Add the cooked fish, diced tomatoes, tomato paste, bay leaves and bone broth to the pot and give it a nice stir. Put the lid back on the pot and set it to "Sealing." Push "Manual" and set the time for just 5 minutes! The Instant Pot will slowly build up to a high pressure point and once it reaches that point, the gumbo will cook for 5 minutes.

Once the 5 minutes have ended, push the "Keep warm/Cancel" button. Cautiously change the "Sealing" valve over to "Venting," which will manually release all of the pressure. Once the pressure has been release (this will take a couple of minutes), remove the lid and change the setting to "Sauté" again. Add the shrimp and cook for about 3-4 minutes, or until the shrimp have become opaque. Add some more sea salt and black pepper, to taste. Serve hot and top off with some cauliflower rice and chives.