Poke the eggplant 2 to 3 times on each side with a knife. Put the eggplant on the rack in a 6 qt Instant Pot and pour 1 cup water into the pot. Follow the manufacturer's guide for locking the lid and preparing to cook. Set to pressure cook on high for 20 minutes.
After the pressure-cook cycle is complete follow the manufacturer's guide for quick release and wait until the quick-release cycle is complete. Being careful of any remaining steam, unlock and remove the lid. Remove the eggplant and rack. The eggplant should be completely soft and deflated. Set aside.
Turn the pot to the high saute setting and when hot, add the oil. Stir in the curry powder, cumin and turmeric and cook until the spices are fragrant, about 30 seconds. Stir in the onions to coat in the oil and spices. Cook, Stirring frequently, until the onions are softened and slightly browned, 7 to 8 minutes. Add the ginger and garlic and stir to coat. Cook until the garlic starts to soften, 1 to 2 minutes more. Add the tomatoes and cook until they break down and lose their structure, 6 to 7 minutes. Add 1 teaspoon salt. Cut the eggplant into chunks. Add the eggplant and peas to the pot and cook until completely warmed through, 2 to 3 minutes. Add additional salt to taste.
Serve warm with rice if desired and sprinkle with cilantro and mint.