Heat the oil in the pressure cooker, then add the cumin and asafoetida. After a minute or so, add the garlic, onion & chilli.
Cook over a medium heat stirring now & again until the onions soften and start to brown. Then add the tomatoes.
When the tomatoes have broken down, check the seasoning then add the turmeric and the drained lentils.
Stir well to coat the lentils with the sauce, then add the water. Turn up the heat and cook under pressure for 12 minutes (high) or 15 (medium). Allow to cool naturally.
Squeeze over some lemon juice and garnish with coriander to serve.