I will be completely upfront about this one: it’s not the simplest recipe. I used a bunch of different spices and it does take a while to cook. However, this is an extremely flexible recipe (when in doubt, just throw in a spice you like and add salt!) and it really feels like you’re spoiling yourself when you first slice into the cooled pie.
Think of this recipe as a basic outline. Use whatever soup, broth, root vegetables, etc. you have on hand to make the lentil filling the consistency you prefer. The second time I made it, I had a bunch of leftover roasted pumpkin and sweet potato soup, so I mixed that in with the lentils and mashed the filling with a fork before baking everything together. You can always add in a cup of pureed pumpkin or a canned soup that has a rich, savory fall flavor to mix with your lentils after they have stewed for a while. It is also a rather flexible recipe. Turnips, beets, and celeriac would all make wonderful additions if they are available to you. If you want a meatier texture, add some soy crumbles in with the mushrooms in the dutch oven and brown them.
The main depth of flavor will come from the red wine and fresh herbs, and when the mashed potatoes mix in the oven with the lentil filling, they will create a really wonderful combination. In this version of the recipe, I roasted thin slices of sweet potato with olive oil and some salt and pepper and pressed them into the bottom of my glass baking dish. The slight sweetness was a wonderful complement to the anise and cinnamon, but a tiny bit of brown sugar, maple syrup, or honey could easily do the trick. If you would like an extra rich flavor, put a thin layer of techina (tahini) on top of the lentils before adding the mashed potatoes.