Sweet Potato Shepherd’s Pie with Red Wine Lentils

For the lentils:
Combine ingredients in medium saucepan and bring to a boil. Reduce heat to a simmer and cook uncovered until just tender, 20–25 minutes. Set aside but do not drain.

For the topping:
Place potatoes and shallot in cold water to cover by a couple inches, in a saucepan, with two teaspoons salt. Bring to boil and cook until very tender, about 8–10 minutes. Drain and return to pan. Use an immersion blender to puree potatoes, then stir in butter, a teaspoon of salt, and a generous pinch of black pepper. Once the potato mixture has cooled at least 10 minutes, stir in egg.

For the filling:
Preheat oven to 400ºF. Heat oil in a large skillet (with a lid) just hotter than medium heat. Add onion, mushrooms, parsnip, squash/turnip and cook until well browned, about 8 minutes. Add tomato paste and garlic and cook another couple minutes. Lots of brown bits will be sticking to the bottom of the pan, which is fine. Add flour and stir until you no longer see white powder. Add wine and thyme, then scrape the bottom of the pan to release the brown bits. Raise heat to bring to a boil, then reduce heat to medium low, cover, and simmer about 10 minutes, stirring often. Add mustard, lentils, and remaining liquid and simmer uncovered until only a little liquid remains, a minute or two. Remove garlic cloves and stir in butter until melted, then season to taste.

To assemble:
Place filling in a lightly oiled 9 to 9½ inch pie plate. Spoon sweet potato mixture over the top (there will be a lot), spread evenly to the edges, and use the tines of a fork (or back of a spoon) to make ridges or swirls that will brown nicely when baking. Bake about 45 minutes just above middle rack position, until top is darkened in places.

Let cool a couple minutes before serving, then garnish with chopped parsley, black pepper, and sea salt.

Note: To make the dish gluten free, omit the flour from the lentil filling and reduce wine quantity to ⅔ cup. It will come out just as good, without the gravy-like thickness associated with traditional shepherd’s pie.