This vegetarian shepherd's pie, packed with lentils, mushrooms, a savory spice mix, and topped with a blanket of mashed potatoes, was such a hit with our community last year that we are bringing it back! Ready in under an hour, this weeknight meal is guaranteed to satisfy meat-eaters and vegetarians alike.
Turn on the oven's broiler and place an oven rack about 6" / 15 cm under the heat source.
Place potatoes into a saucepan and cover with cold water and some salt. Cover and bring to a boil. Simmer uncovered for 12 to 15 minutes until potatoes can be easily pierced by a knife. Drain and let sit in a colander for ~5 minutes to let the steam escape (this creates creamier potatoes vs. liquidy potatoes).
While potatoes are cooking, heat a skillet or saute pan over medium-high heat. Add cooking oil and then mushrooms to heated oil. Saute until mushrooms are deep golden brown, ~5 minutes.
Add onions and saute until softened, 2 to 3 minutes. Add spice mix and saute until fragrant, ~1 minute more.
Add lentils and frozen vegetables and saute to heat through, ~1 minute.
Stir in water, Worcestershire sauce, parsley, and tomato paste.
Transfer filling to a lightly greased 8" x 8" / 20 cm x 20 cm baker (for 4 servings; adjust accordingly if customizing servings).
Use a masher to mash steamed potatoes with yogurt, butter, and some salt. Spoon over top of filling and spread to evenly cover.
Broil for 8 to 12 minutes, until the top is golden brown and crisp.
Whisk together vinegar, mustard, and honey in a mixing bowl. Add olive oil while whisking. Add mixed greens, grapes, and almonds to vinaigrette. Toss just before serving.