Rinse the lentils until the water turns clear.
Peel and dice the pumpkin into small equal sized cubes.
Dice the onion and tomato and mince the garlic.
Add all of the dahl ingredients into a large sauce pan with 800ml water.
Bring to a boil then simmer for 45 minutes to an hour, stirring and checking that its not burning a few times in the process.
Heat the oven to 200C/390F.
Meanwhile make the topping by adding the other half of the diced pumpkin to a baking tray, drizzle with oil and bake for 25 minutes turning half way.
Mash any big bits in the dahl with a potato masher and once a soupy consistency is achieved you’re ready to make the tadka.
Melt the butter in a pan then add the rest of the ingredients and cook on medium heat for 30 seconds.
Serve the dahl topped with the tadka and the roasted pumpkin cubes.