To begin, soak the pear barley for 8 hours or overnight. Wash the dals in water until they run clean. Soak them for 30 minutes. Drain and keep aside.
Heat mustard oil to the smoking point and let it cool a bit. Add bay leaves, whole red chillies, panch phoran, and asafoetida. Allow to crackle.
Add the chopped onions with the slit green chillies and saute until onions are translucent. Add ginger garlic paste and saute for a minute.
Next add the diced vegetables - potatoes, carrots, and cauliflower with the green peas. Mix well and saute for a few minutes.
Add in the tomatoes and saute until they soften.
Now add the dry masalas - salt to taste, black pepper powder, cumin powder, coriander powder, and turmeric powder. Saute for a few minutes. You can add a bit of water to avoid the masalas from burning.
Next, add in the soaked barley with the dals. Mix well and saute for 4-5 minutes.
Add 4 cups water. Bring to a boil. Pressure cook it for 3 whistles. Let the pressure drop completely before opening the cooker. If using an open pot, cook on low heat until the barley is done.
The Assamese-Style Barley Khisiri is ready to serve. Garnish with some more coriander leaves. Serve hot with a dollop of ghee on top.