In a medium saucepan, combine the rinsed lentils, water, and salt.
Bring to a boil over high heat, then reduce the heat to low, cover partially, and let it simmer for about 1 hour. Skim any foam that rises to the surface.
Once the lentils begin to soften, stir in the grated ginger, ground turmeric, crushed cardamom seeds, and cayenne pepper.
Continue to simmer until the lentils are completely tender and have broken down, about 15-20 more minutes. The consistency should be like a thick soup; add a splash of hot water if it becomes too thick.
While the dal finishes simmering, prepare the tadka. Melt the butter in a small skillet over medium heat.
Once it's hot and shimmering, add the crushed red pepper flakes and ground cumin.
Sauté for 30-60 seconds until fragrant and sizzling, being careful not to burn the spices.
Pour the hot, spiced butter (the tadka) directly into the simmering lentils and stir to combine.
Mix in the chopped fresh cilantro and a squeeze of fresh lemon juice.
Serve immediately, hot, with basmati rice or warm naan bread.
Adjust the heat to your liking.
Reduce or omit the cayenne and crushed red pepper for a milder dal, or add more for an extra kick.
Don't skip the final tadka step! Blooming the spices in hot fat is crucial for unlocking their deepest flavors and is the signature of an authentic dal.
