Place potatoes in a large saucepan and cover with water. Sprinkle with salt. Place over medium-high heat. Bring to a boil. Simmer for 4-5 minutes or until potatoes are well cooked. Drain. Mash the potatoes. Set aside.

Meanwhile, place cauliflower in a steamer. Sprinkle with salt. Steam until well cooked.

Heat 2 tablespoon butter in a large pan over medium-high heat. Add onions. Saute for 2 minutes or until onions are soft and translucent. Add garlic. Saute for 1-2 minutes or until aromatic. Add green chilies. Saute again, stirring, for another 1-2 minutes.

Stir in tomatoes and tomato paste (puree). Saute, stirring, for 1-2 minutes or until tomatoes starts to break down. Add bell peppers. Saute until tender. Add pav bhaji masala and red chili powder. Sauté for a minute or until aromatic.

Add mashed potatoes, cooked cauliflower florets and frozen peas. Add enough water to get a semi solid consistency. Season with salt. Scatter over coriander (cilantro) leaves, if you are using. Stir well. Simmer for 3-4 minutes. Transfer the bhaji mixture to a bowl.

Heat 1 tablespoon butter in the same pan over medium-high heat. Slit the pavs in half, and place it in the pan. When one side is brown, flip them over to toast the other side. Set aside.

Serve pav bhaji with chopped onions and lemon wedges.