• Press the SAUTE button on your Instant Pot & set it to NORMAL. It automatically sets for 30 mins.
• Add coconut oil to the pot, when the oil becomes hot throw in the mustard seeds & the dried chilies. Allow them to sizzle for a few seconds.
• Next, add the chopped onion & sweat them off. it should take you about 2 mins. Add salt to catalyze the process.
• Now, add the ginger garlic paste & saute until raw smell of the paste disappears. It should take you another 2 mins or so.
• Throw in all the spices + the tomato puree. Mix & saute for 1 min.
• Add the coconut milk & little water about ½ cup (add more if you like very thin gravy). 
• Cancel the SAUTE mode. Close the lid of the IP, seal the valve by moving it to the SEALING position. 
• Press the PRESSURE COOK button, set the timer for 2 mins & set it on HIGH.
• After 2 mins when the IP starts to beep. Do a QPR (quick pressure release) & open the lid. The curry sauce is ready, it's time to add the fish.
• Now, add the fish fillets. At this point if you feel that the gravy is not enough to hold all the fish fillets just add a little bit water or may be some more coconut milk diluted with water. 
• Close the lid of the IP. Seal the valve. Press the PRESSURE COOK button. Set the timer for 1 mins & set it to HIGH.
• After 1 min when the IP begins to beep. Wait for NPR (natural pressure release) wait until the floating valve in your IP drops. 
• Open the lid carefully. You may garnish with cilantro & slit Indian green chilies if you want. Serve with rice. Enjoy!

Stove top Method

• Follow the same recipe,  replace the Instant Pot with a skillet or Kadai.
• Do the sauteing over medium heat.
• Simmer the curry sauce covered over medium low heat for 5 mins.
• Add the raw fish fillets. Cook everything covered over low heat for 5 mins.
• Garnish with chopped cilantro & green chilies. Enjoy!