Set the Instant Pot in saute mode and add oil.
Once it heats, add the cumin seeds and bay leaf. Saute for a few seconds.
Add onion, ginger, garlic, and green chili.
Saute for 3-4 minutes, until the onions soften and turn translucent.
Add tomatoes, coriander powder, turmeric powder, chili powder, and salt. Mix well.
Saute for 2-3 minutes, until the tomatoes are soft and pulpy.
Add the soaked chana dal and bottle gourd.
Add 1½ cups of water. Mix well and deglaze the pot.
Secure the IP lid and set it to pressure cook mode for 6 minutes.
Do a natural release of pressure for 10 minutes, then do a quick release.
Add garam masala, cilantro, and lemon juice. Mix well.
Serve hot with roti or rice.