Make a mirepoix of onion, carrot and celery, all chopped small, with a little olive oil, Add brown (or green, brown's better though) lentils and enough water to just cover. I use a heavy sauté pan, pop in a couple of bay leaves and then put the lid on and let it all cook just on the simmer until the lentils are soft but not mush. Depends on many factors just how long, but check after 20 minutes and I find mine need just over 25. Adjust seasoning if necessary, salt and black pepper, some folks add some garlic with the bay leaves, and add a good handful of chopped parsley before serving. Classic lentils, pretty much standard European dish.