Vegetable Shepherds Pie

1. Add Ingredients:
2. 12 cups chopped mixed vegetables
3. 1 cup chopped fresh mushrooms
4. 1 cup pearl onions
5. TOPPING:
6. Preheat oven to 450°. Bake potatoes on a foil-lined baking sheet until tender, about 45 minutes. Let cool slightly, then peel. Press potatoes through a ricer, food mill, or colander into a large bowl. Add butter; stir until well blended. Stir in milk. Season to taste with salt.
   45 minutes
7. FILLING:
8. Soak dried porcini in 3 cups hot water; set aside. Combine lentils, 1 garlic clove, 1 tsp. salt, and 4 cups water in a medium saucepan. Bring to a boil; reduce heat and simmer, stirring occasionally, until lentils are tender but not mushy, 15–20 minutes. Drain lentils and discard garlic.
   15–20 minutes
9. Heat 3 Tbsp. oil in a large heavy pot over medium heat. Add onions and cook, stirring occasionally, until soft, about 12 minutes. Add chopped garlic and cook for 1 minute. Stir in tomato paste. Cook, stirring constantly, until tomato paste is caramelized, 2–3 minutes.
   12 minutes1 minute2–3 minutes
10. Add bay leaves and wine; stir, scraping up any browned bits. Stir in porcini, slowly pouring porcini soaking liquid into pan but leaving any sediment behind. Bring to a simmer and cook until liquid is reduced by half, about 10 minutes. Stir in broth and cook, stirring occasionally, until reduced by half, about 45 minutes.
    10 minutes45 minutes
11. Strain mixture into a large saucepan and bring to a boil; discard solids in strainer. Stir cornstarch and 2 Tbsp. water in a small bowl to dissolve. Add cornstarch mixture; simmer until thickened, about 5 minutes. Whisk in miso. Season sauce with salt and pepper. Set aside.
    5 minutes
12. Preheat oven to 450°. Toss vegetables and pearl onions with remaining 2 Tbsp. oil, 5 garlic cloves, and rosemary sprigs in a large bowl; season with salt and pepper. Divide between 2 rimmed baking sheets. Roast, stirring once, until tender, 20–25 minutes. Transfer garlic cloves to a small bowl; mash well with a fork and stir into sauce. Discard rosemary. DO AHEAD: Lentils, sauce, and vegetables can be made 1 day ahead. Cover separately; chill.
    20–25 minutes
13. Arrange lentils in an even layer in a 3-qt. baking dish; set dish on a foil-lined rimmed baking sheet. Toss roasted vegetables with fresh mushrooms and chopped herbs; layer on top of lentils. Pour sauce over vegetables. Spoon potato mixture evenly over.
14. Bake until browned and bubbly, about 30 minutes. Let stand for 15 minutes before serving.
    30 minutes15 minutes

Cooking notes

When scaling protein-led dishes, weigh the meat rather than counting pieces, and remember that the pan size limits how much you can sear at once.

For volume-to-weight conversions of any ingredient — flour, sugar, butter, salts — use the ingredient converter. To translate the recipe's oven temperature between °C, °F and gas mark, see the temperature converter.

When you scale this recipe up or down, remember that cooking time does not scale linearly. A doubled cake takes longer, but not twice as long; a doubled soup takes roughly twice as long. The cooking-time guide gives sensible starting estimates by dish geometry.