Here's a question: I know that lentils cook quickly, so I assume that you just simmer them right in the soup until they're tender rather than pre-cooking them?
Just a note to let you know that I made the soup for supper last night & it was absolutely DELICIOUS!! The only thing I omitted was the mint, since I'm not fond of it in savory applications, & I subbed ground turkey for the lamb. So while perhaps it wasn't "authentic", it sure was good, & I have enough leftover for a couple of lunches or snacks. Thanks again for the recipe.