Start by preparing the lentils. Rinse them thoroughly under cold water until the water runs clear, then set them aside to drain. This step removes excess starch and ensures the lentils cook evenly.
Next, prepare the onion by peeling and finely dicing it into small cubes. Heat the oil in a pan over medium heat. Once the oil is hot, add the diced onion and sauté it for about 3 minutes, stirring occasionally, until it turns translucent and soft.
Add the mustard seeds to the pan with the sautéed onion. Let the seeds toast for around 4 minutes until they start to pop and release their aroma. Stir frequently to prevent them from burning.
Add the curry powder and tomato paste to the pan. Stir them into the onion and mustard seed mixture, allowing the spices and paste to sauté briefly for about 1 minute. This will intensify their flavor.
Now, add almost all of the tomatoes (diced) to the pan, reserving the rest for garnish. Stir the tomatoes into the onion mixture and cook for 2–3 minutes until they soften slightly.
Stir in the drained lentils, vegetable broth, and 125 ml of the oat cream. Mix everything well, then bring the mixture to a boil. Once it starts boiling, reduce the heat to low and let it simmer for about 10 minutes. Stir occasionally to prevent sticking and ensure even cooking.
While the lentils are simmering, prepare the lemon and the remaining garnish. Wash the lemon, then finely grate the zest and juice the lemon into a small bowl. Set the zest aside for the lemon-infused cream and the dal.
Mix the remaining 25 ml of oat cream with the lemon zest in a separate bowl to create a tangy lemon cream for topping. Dice the remaining tomatoes if not already done and set them aside for garnish.
Once the lentils are tender and the dal has thickened slightly, stir in the lemon juice. Allow the dal to warm through for an additional 2 minutes, then season to taste with salt and pepper.
To serve, ladle the dal into bowls. Top each serving with a dollop of the lemon-infused cream, the remaining diced tomatoes, and a sprinkle of freshly chopped cilantro.
