In a high-sided skillet with a lid, add the onion with a bit of olive oil over medium heat. Cook the onion for 5 minutes or until translucent and just barely brown at the edges.
Add the garlic, ginger, tomatoes, and all of the spices to the skillet with a sprinkle of salt. Stir to form a paste and let the spices cook for two minutes.
Add the stock and lentils to the pan. Stir to distribute the spices into the liquid, then reduce the heat to low. Cover the pot and cook for 10 minutes.
After 10 minutes, stir the lentils and taste them; add more salt to your preference. Cover the pan again and let the lentils cook for 5-10 minutes more or until they are cooked through and tender and most of the liquid has been absorbed.
Note that if you have a different type of lentils, cook time or amount of liquid needed may be slightly different. Adjust per the package you have.
Serve with cilantro, lemon or lime wedges, and a bit of rice or naan.