This salad is best enjoyed slightly warm or at room temperature, so if you make it in advance, take note of that before serving. You could substitute in other veggies you’re particularly excited about or bulk it up with leftover grains. And a quick note on the dressing: at first you may feel like there’s an awful lot of it here, but trust that the lentils soak it up.
Rinse the lentils and put them in a saucepan filled with salted water. Add the bay leaf and bring to a boil. Decrease the heat to a simmer, and cook for 20-25 minutes, or until lentils are tender yet chewy (check them often so as not to overcook).
While the lentils are cooking, prepare the other veggies: In a large sauté pan, warm the olive oil over medium heat. Add the leek and asparagus, sprinkle with salt and give them a good stir, and cook for 5-7 minutes. or until asparagus is tender. Add the garlic and cook an additional 2 minutes.
Make the dressing: In a small bowl, whisk together the oil, vinegar, honey, mustard, salt, shallot and pepper.
When the lentils are done cooking, drain them and scoop into a large salad bowl. Remove and discard the bay leaf. Fold the asparagus mixture into the bowl and dress while everything is warm.
Taste and adjust the seasoning, adding more salt and pepper if desired.
Fold in the parsley, tarragon and walnuts. Serve warm or at room temperature. Store leftovers in a covered container in the refrigerator for up to four days.