To prep sweet potatoes for topping, preheat oven to 400 degrees. Place sweet potatoes in oven (on or over a piece of foil to catch any drippings) and roast for about 45 minutes or until easily pierced with a fork. Set aside until cool enough to handle. Reduce oven heat to 350 degrees.
2-3 medium sweet potatoes
Meanwhile, prepare the filling. Heat olive oil in a large skillet over medium high flame. Add onion and garlic then cook for about a minute.
2 teaspoons olive oil, 3 cloves garlic, ⅓ yellow onion
Add ground lamb to pan and break up with spoon then add spices, stir to mix, and cook until lamb is browned.
1 pound ground lamb
Add peas & carrots, mushrooms, tomato paste, and water to pan then stir until the water and tomato paste combine into a sauce. Remove pan from flame and spread filling into a baking dish.
½ teaspoon ground coriander, ½ teaspoon ground cumin, ½ teaspoon kosher salt, ½ teaspoon smoked paprika, ¼ teaspoon black pepper, ¼ teaspoon cinnamon, ¼-1/2 teaspoon crushed red pepper, 1 can Libby's Peas & Carrots, 4 white mushrooms, ½ cup water, 3 tablespoons tomato paste
To make the topping, peel and mash the roasted sweet potatoes. Add black pepper, garlic powder, and salt then mix well. This step should be easy to do with a fork or wooden spoon but can also be accomplished in a food processor or stand mixer.
¼ teaspoon black pepper, ½ teaspoon garlic powder, ½ teaspoon kosher salt
Spread sweet potato topping over filling in pan. If you want, you can make a design in the topping using a large fork, kabob skewer or something similar.
Bake shepherd's pie, uncovered, about 30 minutes. Top will not brown much. Garnish with chopped mint leaves, if desired, and enjoy warm.
fresh mint leaves, chopped