Ingredients:

  • 1 lb Cremini mushrooms, finely diced
  • 1 tbsp unsalted butter
  • 1 tbsp olive oil
  • 1 medium yellow onion, diced
  • 3 medium carrots, diced
  • 2 cloves garlic, minced
  • 2 tbsp tomato paste
  • 1 tsp dried thyme
  • 1 cup frozen peas
  • 1.5 cups vegetable broth
  • 1 tbsp soy sauce
  • 0.5 tsp salt
  • 2 lbs Yukon Gold potatoes, peeled and cubed
  • 4 tbsp unsalted butter
  • 0.5 cup whole milk
  • 0.25 tsp nutmeg
  • 0.5 tsp salt

Instructions:

  1. Melt 1 tbsp butter and olive oil over medium-high heat. Add the diced mushrooms in a single layer; sear without stirring for 3 minutes, then stir and cook for another 5 minutes until mahogany-colored.
  2. Add the diced onion and carrots to the mushrooms, sautéing until softened, approximately 5 minutes.
  3. Stir in the minced garlic, dried thyme, and tomato paste. Cook for 2 minutes until the paste darkens to a brick-red color.
  4. Pour in the vegetable broth and soy sauce, scraping the bottom of the pan to release browned bits. Simmer for 10 minutes until the liquid has reduced by a third and looks glossy. Stir in frozen peas at the end.
  5. While the filling simmers, boil the cubed potatoes in salted water until tender. Drain and mash thoroughly.
  6. Whip the mashed potatoes with 4 tbsp butter, whole milk, nutmeg, and salt until velvety.
  7. Transfer the filling to an oven-safe skillet or baking dish. Spread the potato mash evenly over the top.
  8. Bake in a preheated oven until the potato peaks are golden brown and shattering.