Dal stays hard after frying tarka I have a problem with hard dal after frying. Can someone explain the cause.

I made a tarka for lemon rice yesterday and added 1 tsp of urid dal to the frying mixture as called for in the recipe. Left out the 1 tsp toor dal cos they are bigger and I couldn't imagine that they would cook. On eating, the dal was very hard and weird in the rice. Like eating uncooked rice with cooked rice.

My friend made this recipe before (and used toor dal as well) and when we ate it, I did not notice any hard bits (and I ate the rice for a couple of days after that). I asked her and she said she doesn't know why it became hard. She has also encountered the same problem.

Should the rice be left to steam further after mixing in the tarka?
Generally you have to soak lentils for many hours, use a pressure cooker to soften them up or a combination of the two. Only masoor dal can be cooked straight away. So I'm guessing you missed a step in whatever recipe you are following.