02Meanwhile, place the lentils, carrot, onion, bay leaf, parsley, thyme and 1/2 teaspoon salt in a small pot and add water to cover the lentils by about 3/4 of an inch. Bring to a boil, then simmer, covered, until the lentils are tender, 20 to 25 minutes. Discard the herbs, drain well and transfer to a large bowl.03To make the vinaigrette, combine the lemon juice, zest, shallot and 1/4 teaspoon salt and let stand for 15 minutes. Whisk in the olive oil and season to taste with pepper and more salt if necessary.04To assemble the salad, quarter the lemon and scrape out the soft pulp. Finely chop the pulp and stir 2 teaspoons into the vinaigrette. Finely chop the lemon skin and add it, along with the vinaigrette, roasted beets, parsley and chopped mint, to the lentils. Toss and serve on a platter. Grate the reserved beet and use it for garnish with mint sprigs.