Set the Instant Pot to sauté and heat the olive oil.
Add onion, carrots, celery, and salt. Cook for 8–10 minutes until softened.
Stir in cumin, chilli powder, turmeric, and tomato paste. Cook for 1–2 minutes.
Add broth, water, lentils, and bay leaf. Stir to combine.
Seal the lid and cook on high pressure for 10 minutes.
Allow natural pressure release, then open and stir.
Remove the bay leaf and stir in lemon juice.
Blend partially or fully if you prefer a smoother consistency.