Mix together all the shrimp marinade ingredients and let the shrimp sit until you are ready to cook.
Rinse the rice thoroughly until the water runs almost clear. Soak the rice in cold water for 20 to 30 minutes.
Make the Masala (Sauce)
Gather the rest of the ingredients.
While the rice is soaking, heat an Instant Pot on the sauté setting, add 2 tablespoons of ghee or coconut oil. When it is hot, cook 1 tablespoon of whole cashews. Stir for a minute or two until the cashews are getting a few brown spots. Add the raisins and sauté another couple of minutes until the raisins have plumped up and the nuts are golden brown. Remove and set aside.
Add the onions to the Instant Pot and the whole spices and cook frequently stirring for about 5 to 10 minutes until the onions are golden brown.
Stir in the ginger garlic paste and cook for a minute or two until the paste no longer smells raw. Stir in the green chili, diced tomatoes, and ground spices. Sauté the tomatoes about 3 minutes until they become mushy.
Drain the rice and add to the Instant Pot. Stir in the lemon juice, cilantro, and mint. Add 3/4 cup of water or more, if needed, to almost submerge all the rice. See Notes about the amount of water required. Place the shrimp on top of the rice.
Secure the Instant Pot lid, close the pressure valve, and cook for 5 minutes on low pressure. See Notes below if you don’t have a low-pressure option.
Carefully quick-release the pressure. When it is safe, open the lid and drizzle the biryani with a tablespoon of ghee if using. Keep the lid on but opened slightly so the steam is able to continue to escape. Rest the biryani for 5 minutes, then using a fork gently combine the shrimp and rice.
SHORTCUT: Buy or have your fishmonger shell and clean the shrimp. It is not necessary to defrost the shrimp unless you need to clean and devein.
It is essential to use large shrimp so they don’t overcook.
There is no need to defrost the shrimp if they are already shelled and deveined.
If you don’t have a low-pressure function on your pressure cooker, use the high-pressure mode for 4 minutes. Cooking on high pressure requires more liquid to pressurize, so use a full cup of water. Refer to your manual when using a different brand of pressure cooker for the liquid requirements. Pressure release naturally for 10 minutes, then open the pressure valve to let the remaining pressure escape. This will allow the rice to finish cooking. Follow the rest of the instructions as listed above, beginning with opening the lid and adding the optional ghee.
To make extra special shrimp biryani, find some premium aged basmati rice. It cooks up into long beautiful fluffy grains. Or even the traditional rice from Kerala called Jeerakasala or Wayanadan kaima. No need to soak it, though.
If cooking on low pressure, you only need to use enough water so that the rice is just about submerged. Using too much water will result in a mushy mess. I find that on low-pressure 3/4 of a cup of water is enough. You also have lemon juice, juicy tomatoes, and some residual water from the rice that brings the liquid up to the required 1 cup for the Instant Pot. If you are using another brand of a pressure cooker, use their guide for the amount of water needed. Keep in mind that there are about 3 to 4 tablespoons of liquid in those ingredients. Cooking on high-pressure will require more liquid than low-pressure.