Remove the leaves from the siru keerai. You can even use the tender stems. Wash and chop the siru keerai.
In a pressure cooker, take the keerai, dal, turmeric powder, red chilli powder, onion, tomato and salt. Add sufficient water and close the lid. Cook till the dal is done.
Allow the steam to escape and mash the keerai and dal lightly with a wooden masher or hand blender.
Heat oil in a pan, add mustard seeds.
When the mustard seeds begin to splutter, add the cumin seeds, garlic and whole dry chili. Add this tempering to the prepared keerai.
Serve hot with plain rice.