Select sauté on the instant pot and adjust to normal.
Add 2 tbsp ghee to the pot.
When the ghee is hot add the chopped onions. Stir occasionally in order to prevent the onions from burning.
When the onions turn golden in about 2 to 4 minutes add the ginger garlic paste. Stir.
Then add the diced tomatoes and let them sauté until they get mushy, for 3 to 4 minutes. Keep stirring.
Then add the black pepper, coriander, cumin, garam masala, red chili powder, salt, and ¼ cup water. Stir.
Press cancel.
Let the mix cool for about 5 minutes and grind the sautéd mixed ingredients along with the cashews into a fine paste in a coffee blender. Transfer in a bowl.
Wash the inner pot and dry it with a napkin.
Select sauté on the instant pot and adjust to normal.
Add the remaining 2 tbsp ghee to the pot.
When the ghee is hot add the bay leaves, crushed mace and cloves, cardamoms, and cinnamon stick. Sauté for a minute.
Add the crushed spice and cashew mix. Stir.
Then add the mushrooms and stir. Add the remaining ¼ cup water. Make sure nothing is stuck to the bottom of the pot and scrape the bottom of the pot well.
Press cancel.
Secure the lid on the pot and close the pressure-release valve.
Select manual and cook at high pressure for 7 minutes.
When cooking is complete, use quick pressure release to depressurize.
Open the lid.
Select sauté and add the whisked yogurt slowly (one spoon at a time) to the pot mixing it continuously.
Then add the heavy whipping cream and keep mixing.
Add dried fenugreek leaves and stir. If you like less gravy, let some gravy evaporate. I personally like some gravy in mushrooms.
Press cancel when the desired consistency is reached.
Transfer the cooked mughlai mushroom in a serving bowl and discard the bay leaves.