1. Make the bouquet garni by placing the parsley, thyme, bay leaves and peppercorns in a 6-inch cheesecloth square (you’ll need to sort of fold the parsley branches). Pull the ends up to make a little bag and tie it closed with kitchen string.

2. Halve the onions lengthwise and stud each half with 2 cloves.

3. Place the lentils in a medium cooking pot with enough water to cover by 2 inches. Add the bouquet garni and clove-studded onion halves. Place over high heat and bring to a boil. Lower the heat to a simmer and simmer, uncovered, until the lentils are almost tender, about 20 minutes.

4. As the lentils cook, heat the oil in a heavy skillet over medium heat. When the oil is good and hot, add the tempeh strips and sear, turning once, until the tempeh is browned, 3 to 4 minutes on each side. Remove the tempeh from the skillet and let cool slightly. When cool, slice into 1-inch pieces. Set aside. Do not discard the oil.

5. Return the skillet and oil to medium heat. Add the leeks and sauté until softened but not colored, about 4 minutes. Add the carrots and celery and sauté until the vegetables have softened, 3 to 5 minutes. Add the garlic and cook for 30 seconds. Remove from the heat and set aside.

6. Back at the lentil pot. Using a pair of tongs, fish out and discard the clove-studded onion pieces and the bouquet garni. Stir the sautéed vegetables and any oil clinging to them into the lentils. Continue cooking the lentils until tender, another 10 to 15 minutes. Stir in the reserved tempeh. Add salt and pepper to taste and serve hot or at room temperature.