This is the recipe I follow for dal/dhal/dahl/daal tadka/tarka. “Tadka” is a tempered spice-and-oil topping that you add before serving to enhance the flavours of the dal. The ingredients and method are based on one of the dal tadka recipes on the excellent site Vegetable Recipes of India (see recipe). It would be best to use arhar or tuvar dal, but I use red lentils generally since they’re the easiest to find and still taste great. This serves 4 people and is excellent with jeera rice.

Dal tadka, serves 4

Dal ingredients

1 c red lentils
1 chopped onion
2 chopped tomatoes
1 t red chilli powder
½ inch ginger finely chopped
1 t turmeric powder
pinch of asafoetida
¼ t fenugreek
¼–½ t smoked paprika
4 c water
2 T plain yogurt
1 T chopped coriander (cilantro) leaves
Generous pinch garam masala
About 1 t salt to season

Tadka ingredients

2 T vegetable oil
1 t cumin seeds
1 t mustard seeds
5–6 garlic cloves, finely chopped
1 ½ t red chilli powder, more to taste
Generous pinch asafoetida
8–10 curry leaves

Method

Rinse the lentils and add them to a large pot. Add the chopped onions, tomato, chilli powder, ginger, turmeric, asafoetida, fenugreek, smoked paprika, and 4 cups of water to the pot. Stir well, bring it to a boil, and then reduce the heat to simmer. Simmer the lentil mixture until it reaches the desired consistency, stirring occasionally and adding water if required.
While the dal reduces, prepare the tadka. Heat the oil in a nonstick pan. Add cumin and mustard seeds and cook until popping, being careful not to burn them. Add chopped garlic, red chili powder, asafoetida, and curry leaves. Reduce the heat to low or off so as not to burn the garlic. Brown the mixture thoroughly, then set the tadka aside.
When the dal has reached the correct consistency and the tadka is prepared, stir the yogurt, garam masala, chopped coriander leaves and salt in to the dal. Pour all of the tadka, including the oil, over the dal. Serve the dal tadka with the tempering on top, or feel free to mix it in.