Set your Instant Pot to 'Sauté' mode and add olive oil to the pot.
Once the oil is hot, add diced onion and sauté for about 3 minutes until translucent.
Stir in minced garlic, grated ginger, cumin, coriander, and cayenne pepper. Cook for an additional 1-2 minutes until fragrant.
Add the chopped carrots and vegetable broth to the pot, stirring to combine.
Close the lid, ensuring the steam valve is set to 'Sealing.' Select 'Pressure Cook' or 'Manual' and cook on high pressure for 10 minutes.
Once cooking is complete, carefully perform a quick release of pressure by moving the steam valve to 'Venting.'
Open the lid and stir in the coconut milk. Use an immersion blender to blend until smooth, or transfer to a traditional blender.
Season the soup with salt to taste and add lime juice for extra brightness if desired.
Serve hot, garnished with fresh cilantro if desired.