Combine : Place the 6 cups (1440 ml) / 1. 5 L of hot water, all prepared vegetables, the mixed whole grains, and the drained split peas into a 6-quart pressure cooker.
Add Spices: Add the ground coriander, turmeric, minced fresh ginger, 1 tbsp (15 ml) of the butter, and 2 tbsp (30 ml) of the fresh herbs to the pot.
Bring to Pressure: Secure the lid on the pressure cooker and place it over high heat until the pressure regulator begins to rock.
Cook the Soup: Reduce the heat to moderate, allowing the regulator to rock gently, and cook for exactly 20 minutes.
Release Pressure: Remove the pan from the heat and allow the pressure to drop naturally.
Once depressurized, carefully remove the lid.
Finish and Season: Stir in the salt, the remaining 2 tbsp (30 ml) of butter, and the crushed roasted cumin seeds.
Serve and Garnish: Ladle the hot Sabji Shorba into warmed soup bowls and garnish with the remaining 2 tbsp (30 ml) of fresh coriander or parsley just before serving.