Soak Lentils: Rinse lentils and leave to soak in plenty of water for 1 hour. Drain in colander.

Heat ghee/oil in a heavy based saucepan over high heat. Add green chillies and fry for a minute until starting to blister.

Add onions and fry until softened.

Lower heat to medium, add garlic, ginger and curry leaves. Cook for 1 minute until garlic starts to turn golden and smells amazing.

Add tomatoes and cumin, cook until tomatoes start to break down and thicken to a paste - about 2 minutes.

Add lentils, water, tumeric and salt. Stir, bring to simmer, cover and simmer gently for 1 hour. Stir two or three times during the hour.

Remove lid and simmer gently for 30 minutes to thicken, stirring every now and then. The dal is ready when it has a consistency like porridge - some lentils should be intact but some have broken down to thicken the sauce.

Stir through garam masala at the end. Adjust salt if desired.

Pour over Tadka, if using, and stir through.

Serve Dal over rice, garnished with a sprig of coriander if desired.

Heat ghee in a small pan over medium heat until hot but not smoking.

Add cumin and mustard seeds, stir until cumin is slightly golden.

Then add chillies and cook for 20 seconds, then add eschallots and cook until tinged with gold. Don't let the spices burn!

Immediately pour into Dahl.