There are many ways to cook tadka dal or dal fry but this is the one I use as it suits our palate. Tadka means tempering and I have used a standard Punjabi tadka with few variations. You can avoid adding tomato and can use lime juice instead. It won't matter much to the taste. You can also skip onion if you want.
Recipe of tadka dal/ dal fry
1 cup dhuli moong dal (split, skinless green gram) or dhuli masoor dal (red lentils)
1 onion- chopped
1 medium tomato- diced
2-3 green chillies- chopped
2-3 cloves garlic- crushed
1 tsp cumin seeds
1 tsp mustard seeds
A pinch of hing (asafoetida)
1/2 tsp turmeric powder
1 tbsp ghee (clarified butter)
Salt to taste
Chopped coriander leaves (cilantro) - for garnish
1. Cook the dal with salt, turmeric powder and enough water in a pressure cooker till just done. Dal should not be too mushy.
2. Heat ghee in a pan and add cumin seeds and mustard seeds. When they splutter, add hing.
3. Add onion and sauté till transparent. Add garlic and green chillies and fry for 1 minute.
4. Add tomato and cook till tomato become soft and pulpy. Pour this tadka or tempering over the cooked dal. Garnish the dal tadka with coriander leaves. Serve hot with rice or roti.