Wash 3/4 cup of toor dal thoroughly.
In a large saucepan, combine the washed toor dal, 1 chopped bunch of spinach, 2 medium chopped tomatoes, 1/2 medium chopped yellow onion, and 2 sliced green chilies.
Cook the mixture over medium-high heat until the lentils are very tender, approximately 30 minutes.
In a separate pan, heat 1 teaspoon of oil and add 1 teaspoon each of mustard seeds and cumin seeds.
Once the mustard seeds start popping, add 4 minced red chilies and 15 curry leaves.
Sauté for 35 seconds and then pour the cooked dal mixture over the spices.
Add 1 teaspoon of red chili powder, 1 teaspoon of garam masala, 1 teaspoon of turmeric, 1/2 teaspoon of sugar, and 1/2 teaspoon of salt to taste. Mix well.
Cover the pan, bring the mixture to a boil, and then let it simmer for 2-3 minutes.
Stir in the juice of 1 lemon and turn off the stove.
Serve the Dhal Palak hot with rice.