How to Make It
In a large saucepan, cover the lentils with cold water and bring to a simmer. Cook over moderately low heat, stirring occasionally, until the lentils are tender, about 18 minutes. Drain the lentils well and transfer to a large bowl.
Meanwhile, in a medium saucepan, cover the potatoes with cold water and bring to a boil. Cook over moderately high heat until the potatoes are tender, about 10 minutes. Drain very well and add to the lentils. Add the scallions, tomatoes, parsley, mint, garlic, olive oil and lemon juice, season with salt and pepper and toss. Spoon the lentil salad onto plates and top with the goat cheese. Serve at once.