Add the rinsed red lentils, coconut milk, vegetable broth, cumin, turmeric, cayenne pepper (if using), salt, and black pepper to the inner pot. Stir well to combine everything.
Secure the lid and set the vent to Sealing. Select the Manual or Pressure Cook setting and cook on High Pressure for 6 minutes.
When the cooking cycle finishes, allow for a Natural Pressure Release (NPR) for 10 minutes, then carefully move the valve to Venting to release any remaining pressure.
Open the lid. Stir the lentil mixture. It will be thick.
Stir in the chopped spinach until it wilts completely, which takes about 2 minutes.
Stir in the lime juice. Taste and adjust salt and pepper as needed before serving.
Notes
Rinsing the red lentils removes excess starch, which helps prevent foaming during pressure cooking.
For a thicker consistency, you can cook for 1 minute longer on high pressure or let it sit on the Keep Warm setting for 10 minutes after the initial release.
If you do not have fresh ginger, use 1/2 teaspoon ground ginger instead.