Select Sauté, Normal / Medium setting on the Instant Pot. Lightly toast each spice, one at a time, by adding it to the pot and stirring continuously until aromatic, about 1 minute each. Make sure not to burn them. The goal is to remove any residual moisture so they are easy to grind.
As the spices are toasted, transfer them to a plate and let cool completely. Grind the spices in a spice grinder to make a fine powder.
Store in an airtight container in a cool, dry place away from direct sunlight for up to 6 months.
In a bowl, combine the chickpeas and 2 cups warm water and let soak for at least 4 hours or up to overnight. Drain the chickpeas and set aside.
Select Sauté, High setting on the Instant Pot and heat the ghee. Add the cumin seeds directly to the hot oil at the bottom edges of the pot and cook until they start to sizzle, about 1 minute. Add the onion and cook, stirring occasionally, until translucent, about 5 minutes. Cover the pot with a glass lid (or other nonlocking lid that fits) to speed up the process. Add the ginger and garlic and sauté until aromatic, about 1 minute. Add the coriander, salt, chili powder, turmeric, and chickpeas; pour in the 1 1/2 cups water; and stir well with a wooden spoon, nudging loose any browned bits from the pot bottom.
Pressure Cook on High for 35 minutes. When the time is up, allow for 10 minutes natural release, then carefully quick-release the rest of the pressure.
Select Sauté, More / High setting. Then add plum tomato to the inner pot and garam masala. Cook until softened while stirring occasionally, about 5 minutes. Serve and sprinkle with cilantro.
Notes
VEGAN VARIATION Substitute neutral vegetable oil or coconut oil for the ghee.
Use 1 teaspoon Kashmiri red chili powder for a milder curry, or 2 teaspoons for a spicier curry. Organic chickpeas or older beans may need an extra 5 to 10 minutes of cooking time.