Mix all muthiya ingredients with water to form a stiff dough. Shape into small cylinders and lightly fry until golden. Set aside.
Blend all green masala paste ingredients with minimal water to form a smooth paste.
Parboil purple yam, sweet potato, and raw banana until 70% cooked. Partially cook beans and peas separately.
In a heavy-bottomed pot, layer the parboiled vegetables, beans, and peas.
Add the fried muthiya and spread green masala paste over the vegetables.
Mix all undhiyu masala ingredients and sprinkle evenly over the layered vegetables.
Drizzle oil around the edges and add ¼ cup water if needed.
Cover tightly and cook on low heat for 30-35 minutes until all vegetables are tender.
Gently mix before serving and garnish with fresh coriander.