Prepare the lentils for the salad: Rinse, and boil in a pan of water for 2-3 minutes. Drain the lentils and discard the water. Put the lentils to boil again.
Add the stock cube, sprig of thyme and bay leaf. Boil for approximately 20 minutes until the lentils are al dente. Take care not to overboil as they will become mushy. The lentils need to have a bit of a bite for the salad.
Put the couscous in a bowl and pour over just enough hot water to cover. Set aside for 10 minutes then fluff up the couscous with a fork.
Put all the remaining ingredients (except those for the dressing) in a bowl. Mix together and season with salt and pepper.
Mix all the dressing ingredients together in a bowl and pour over the salad