Creamy Mushroom Leek Pie (Printable)

Rich mushroom and leek filling topped with creamy mashed potatoes, perfect for a warm, hearty main dish.

# What You Need:

→ Potato Topping

01 - 2.6 lbs Yukon Gold potatoes, peeled and cubed
02 - 1/4 cup whole milk
03 - 1/4 cup unsalted butter
04 - 1/2 cup grated Parmesan cheese (optional)
05 - Salt and freshly ground black pepper, to taste

→ Filling

06 - 2 tbsp olive oil
07 - 1 medium onion, finely chopped
08 - 2 large leeks, white and light green parts only, cleaned and sliced
09 - 3 garlic cloves, minced
10 - 1.1 lbs cremini or button mushrooms, sliced
11 - 2 medium carrots, diced
12 - 2 celery stalks, diced
13 - 1 tsp fresh thyme leaves (or 1/2 tsp dried thyme)
14 - 2 tbsp all-purpose flour
15 - 3/4 cup vegetable broth
16 - 3/4 cup heavy cream
17 - 1 tbsp soy sauce
18 - 1 tbsp chopped fresh parsley
19 - Salt and freshly ground black pepper, to taste

# Steps:

01 - Preheat the oven to 400°F.
02 - Place the potatoes in a large pot, cover with salted water, and bring to a boil. Cook until fork-tender, about 15-20 minutes. Drain well.
03 - Mash the potatoes with milk, butter, Parmesan cheese (if using), salt, and pepper until creamy and smooth. Set aside.
04 - While the potatoes cook, heat olive oil in a large skillet over medium heat. Add onion and cook for 3 minutes. Stir in leeks and garlic; cook for another 3-4 minutes until softened.
05 - Add mushrooms, carrots, and celery. Sauté until mushrooms are browned and vegetables are tender, about 8-10 minutes.
06 - Sprinkle flour over the vegetables and stir well to coat. Cook for 1 minute.
07 - Gradually add vegetable broth, stirring to prevent lumps. Pour in heavy cream, soy sauce, and thyme. Simmer until thickened, about 5 minutes.
08 - Season filling with salt, pepper, and parsley. Remove from heat.
09 - Spoon the mushroom and leek filling into a 9x13-inch baking dish. Spread the mashed potatoes evenly over the top.
10 - Use a fork to create ridges on the potato surface for extra crispiness. Bake for 25-30 minutes, or until the top is golden brown and the filling is bubbling.
11 - Let rest for 10 minutes before serving.

# Expert Hints:

01 -
  • The mushroom filling develops this deep, savory richness that even meat lovers request seconds of
  • Everything comes together in one dish with minimal cleanup on busy weeknights
  • Leftovers reheat beautifully and somehow taste even better the next day
02 -
  • Let the filling cool slightly before topping with potatoes so they don't get watery
  • Creating ridges with your fork is essential for getting those crispy golden bits everyone fights over
  • The 10 minute rest period is non negotiable or it will ooze everywhere when you serve it
03 -
  • Dry your mushrooms with a paper towel before cooking so they brown instead of steam
  • Warm your milk slightly before mashing to keep the potatoes hotter and smoother