Precook the toor dahl in a pressure cooker with 4 cups of water for 20 minutes or boil on the stovetop in a heavy-bottom pan until soft.
Whisk the dahl until smooth and thin it out with ½ cup or more of water until its consistency is similar to heavy cream. Set aside.
In a heavy-bottom saucepan, warm the ghee (or butter) until it is melted and add cumin seeds.
As the seeds begin to sizzle, add the cashew halves and lightly sauté them until they are golden.
Remove the cashews from the ghee and save them for topping the daal.
Add the slivered onions to the remaining ghee and sauté them until they are lightly golden brown.
Add the garlic cloves, cloves and broken pieces of red chilies, and sauté for ½ minute. Take care at this point, as the cloves are likely to pop and sputter out of the pan.
Add the turmeric powder and squash of your choice and stir until the squash is coated with the spices.
Cook the squash on medium-low for 2-4 minutes until the edges are browned.
Slowly pour the cooked and whisked dahl into this compote and stir in to ensure that the dahl does not stick to the bottom of the saucepan.
Add water as needed to make a smooth consistency and to allow the dahl to boil, the squash to cook and the flavors to combine. Since all the ingredients are mostly precooked at this point, the boil is only intended to help the squash cook through.
Stir every 1-2 minutes to prevent the daal from sticking to the bottom of the saucepan.
Finish the dahl with lemon juice and salt, and sprinkle with cilantro leaves and reserved cashew for a final garnish. Enjoy hot.