Use tiny French green, Spanish Pardena, or black lentils for this salad, and be careful not to overcook them. It’s worth the effort to use all of the aromatics in the cooking broth for tons of flavor inthe finished lentils. The salad taste great at room temperature.
In a medium pot, cover the lentils by about 1 ½ inches with cold water. Add the onion, parsley, thyme, bay leaf, and garlic clove. Bring to a boil over high heat, then reduce heat to medium-low and simmer for about 10-15 minutes, until the lentils are tender.
In a small bowl or glass jar, make the dressing. Add the mustard, vinegar, olive oil, shallots, salt and pepper. Whisk or shake until combined.
Drain lentils, then remove and discard bay leaf, thyme, parsley, and onions. Dress the warm lentils with the dressing and add the shallots. Taste and adjust seasoning. Serve at room temperature.