Foolproof Savory Shepherd'S Pie

• 4 ounces button mushrooms
• 1/2 yellow onion
• 1 stalk celery
• 1 carrots
• 1 tablespoon butter
• 1 tablespoon olive oil
• 1 teaspoon salt divided
• 1/4 teaspoon black pepper
• 1 1/2 pounds lean ground beef
• 1 teaspoon dried thyme
• 1 dash nutmeg
• 1 teaspoon worchestershire
• 1 tablespoon tomato paste
• 1/3 cup frozen peas
• 1/3 cup frozen corn
• 2 tablespoons all-purpose flour
• 1 cup beef broth
• 2 pounds yukon gold potatoes
• 1/4 cup unsalted butter
• 1/4 cup sour cream
• 1 teaspoon salt
• black pepper
• 2 tablespoons milk

1. Preheat the oven to 425u0b0 F.
2. Spray a 9" pie plate with non-stick cooking spray. Set aside.
3. Thinly slice the mushrooms. Finely dice the onion, celery, and carrot.
4. In an extra-large skillet over medium-high heat, melt the butter.
5. Add the mushrooms to the skillet and season with 1/4 tsp. salt.Saute for 5-6 minutes, stirring frequently, until the mushrooms have released their juices and are nicely browned.
6. Transfer the mushrooms into a bowl and set aside.
7. Pour the olive oil into the pan. Once the oil is shimmering, add the onions, carrots, and celery.
8. Saute the vegetables oven medium-high heat for 7-8 minutes, stirring frequently, until they are soft and translucent.
9. Add the lean ground beef, thyme, nutmeg, 3/4 tsp. salt, and black pepper to the skillet.
10. Saute the beef over medium-high heat for 7-8 minutes, breaking it up with a wooden spoon as it cooks, until browned and cooked through.
11. Return the mushrooms to the skillet.
12. Add the Worcestershire sauce, tomato paste, corn, and peas to the pan. Stir for about two minutes, until the sauces are evenly distributed throughout the beef mixture and the corn and peas are thawed.
13. Reduce the heat to medium. Sprinkle the flour over the beef mixture. Cook for one minute, stirring constantly to incorporate and toast the flour.
14. Slowly stream the beef broth into the pan. Cook, stirring frequently, for about 2 minutes, until the broth begins to bubble and thicken.
15. Remove the skillet from the heat. Transfer the beef mixture to the prepared pie plate.
16. Peel the potatoes and dice into 1/2" cubes.
17. Place the potatoes in a large pot. Fill the pot with cold water. Set the pot of water over high heat and bring to a boil.
18. Boil the potatoes for 15-18 minutes, until they can be easily pierced with a fork.
19. Once tender, drain the potatoes in a large colander and return them to the pot. Add the butter, sour cream, salt, and pepper to the potatoes.
20. Mash the potatoes using a potato masher or large fork, until smooth. Add 1 Tbs. of milk to the mashed potatoes and stir gently to combine. If the potatoes seem too thick, add an additional Tablespoon of milk.
21. Spoon the potatoes over the beef mixture. Use the back of the spoon to work the mashed potatoes into an even layer.
22. Place the pie plate on a large baking sheet. Transfer the baking sheet to the middle rack of the preheated oven.
23. Bake the shepherd's pie for 15-17 minutes, until the potatoes are lightly golden and the edges of the pie are bubbling.
24. Remove the pie from the oven. Allow to rest for 7-10 minutes before serving.

button mushrooms, yellow onion, celery, carrots, butter, olive oil, salt, black pepper, lean ground beef, thyme, nutmeg, worchestershire, tomato paste, frozen peas, frozen corn, flour, beef broth, gold potatoes, unsalted butter, sour cream, salt, black pepper, milk

Taken from www.yummly.com/recipe/Foolproof-Savory-Shepherd_s-Pie-9029503 (may not work)