• Heat oil in a pan or skillet.
• Once oil is hot put one teaspoon cumin seeds.
• Let it crackle and then add ginger garlic.
• Sauté till it leaves pungent raw smell.
• Add sliced onions and green chillies.
• Sauté for 2 mins on high flame till its translucent.
• Add chopped tomatoes and saute till it's cooked.
• Now add the spices mentioned above and mix well.
• Add 2 - 4 tbsp water to avoid burning of spices.
• Then add chopped potatoes and eggplants.
• Stir well and cook in high flame for a minute.
• Season with salt as per taste.
• Cover with a lid.
• Cook for  8 - 10 minutes on low flame.
• Check in between by stirring occasionally.
• If required add water 1 - 2 tbsp while stirring to avoid sticking at base.
• Garnish it with freshly chopped coriander leaves and add a dash of lemon juice. 
• Serve hot with roti, paratha or rice.

Instant Pot Method

• Start instant pot at saute mode for 7 minutes.
• Once it's hot, add oil.
• Then add cumin seeds and ginger garlic paste (minced).
• Now add chopped onion and saute for 30 seconds.
• Then add tomatoes and cook for 2 minutes or till cooked soft.
• Add the spices and stir immediately.
• Then add the chopped vegetables and mix well.
• Now deglaze the pot by adding 4 - 5 tbsp water.
• Now cancel the saute mode and start the pressure cook mode.
• Set the timer for 5 minutes at high pressure, and close the lid.
• Set the vent to seal.
• After timer is off, allow it to naturally release pressure for 5 minutes.
• Then release the pressure of the instant pot and open the lid.
• Eggplant & potato curry is ready.
• Remove the inner pot to stop excess cooking from the hot plate.
• Add chopped cilantro leaves and a dash of fresh lemon juice.
• ** To make this a curry consistency, add ¼ cup water.