Set Instant Pot to sauté and add oil to Instant Pot insert.
Once heated, add the onion and 1 tablespoon of water.
Sauté for about 5 minutes until softened.
Switch the Instant Pot off and stir in the garlic, ginger, coriander, cumin, Garam Masala, turmeric and salt. Stir together for about a minute, until fragrant.
Next add in the split peas, tomatoes, and water. Mix, making sure to scrape the bottom of the Instant Pot insert to avoid the burn message.
Add in the coconut milk, but do not stir in.
Place the lid on and turn the value to the sealing position. Set for 9 minutes on high on manual /pressure cook (depending on the Instant Pot model).
When done, allow for a full natural pressure release.
Open the lid, stir, and then ladle into bowls.
10. To serve, swirl in some coconut milk and add some fresh lime wedges.