Pan-Seared New York Strip Steak with Creamy Mashed Potatoes and Roasted Carrots

There’s something special about a perfectly cooked steak and this recipe takes it to the next level. We start with a thick New York strip steak, seared until golden and cooked to your liking. But the magic doesn’t stop there-a luscious mushroom pan sauce, made with beef demi-glace and Dijon mustard, adds deep savory flavor that coats every bite.

On the side, we have ultra-creamy Yukon Gold mashed potatoes, enriched with sour cream and topped with sweet caramelized onions. Tender roasted baby carrots, lightly charred at the edges, complete the plate. This is a hearty, satisfying meal that feels like a special occasion but is simple enough for a weeknight.

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Ingredients

1 unit Yellow OnionView ingredient guideLike ingredientDislike ingredient

2 clove GarlicView ingredient guideLike ingredientDislike ingredient

8 ounce CarrotView ingredient guideLike ingredientDislike ingredient

4 ounce Button MushroomsView ingredient guideLike ingredientDislike ingredient

16 ounce Yukon Gold PotatoesView ingredient guideLike ingredientDislike ingredient

0.25 ounce ParsleyView ingredient guideLike ingredientDislike ingredient

6 tablespoon Sour CreamView ingredient guideLike ingredientDislike ingredient

12 ounce New York Strip SteakView ingredient guideLike ingredientDislike ingredient

1 unit Beef Demi-GlaceView ingredient guideLike ingredientDislike ingredient

1 teaspoon Dijon MustardView ingredient guideLike ingredientDislike ingredient

2 tablespoon Vegetable OilView ingredient guideLike ingredientDislike ingredient

2 tablespoon ButterView ingredient guideLike ingredientDislike ingredient

Salt (to taste)View ingredient guideLike ingredientDislike ingredient

Pepper (to taste)View ingredient guideLike ingredientDislike ingredient

Instructions

1. Preheat the oven to 425°F (220°C) with a rack in the upper position. Wash and dry all produce. Halve, peel and thinly slice the yellow onion. Mince or thinly slice the garlic. Halve the carrots lengthwise through the stems. Thinly slice the button mushrooms. Peel the Yukon Gold potatoes and cut them into ½-inch cubes. Pick the parsley leaves from the stems and finely chop them; discard the stems.
2. On a baking sheet, toss the carrots with a generous drizzle of vegetable oil, salt and pepper. Roast until tender and slightly charred at the edges, about 20-25 minutes. Meanwhile, place the potato cubes in a medium pot and add enough salted water to cover by 1 inch. Bring to a boil and cook until tender, about 15 minutes. Drain thoroughly.
3. While the potatoes cook, heat a large drizzle of vegetable oil in a medium pan (preferably nonstick) over medium-high heat. Add the sliced onion and cook, stirring occasionally, until browned and very soft, about 15 minutes. Add a splash of water every so often to deglaze the pan, scraping up any browned bits. Transfer the caramelized onions to a small bowl and season with salt and pepper.
4. Return the drained potatoes to the empty pot and place over low heat. Mash with a potato masher until smooth. Stir in the sour cream and season with salt and pepper. Keep warm over low heat. Wipe out the pan used for the onions, then heat another large drizzle of oil over medium-high heat. Pat the steak dry with paper towels and season generously with salt and pepper. Add the steak to the pan and cook to your desired doneness, about 3-6 minutes per side for medium-rare.
5. Remove the steak from the pan and let it rest on a cutting board. Add the butter and sliced mushrooms to the same pan over medium-high heat. Cook, tossing, until the mushrooms are softened, about 2-4 minutes. Add the garlic and cook until fragrant, about 1 minute. Stir in the beef demi-glace and ¼ cup of water, then bring to a boil. Reduce the heat to a simmer and stir in the Dijon mustard. Let the sauce simmer until slightly thickened, about 1-2 minutes. Remove from heat and stir in half of the chopped parsley. Season with salt and pepper.
6. Divide the mashed potatoes and roasted carrots between plates. Spoon the caramelized onions over the potatoes. Slice the rested steak against the grain and arrange on top of the potatoes and onions. Spoon the mushroom sauce over the steak, making sure to include the mushrooms. Garnish with the remaining parsley.

Recipe Tips

FAQ

Can I use a different cut of steak?

Yes, ribeye or sirloin work well, but adjust cooking time based on thickness.

Can I make the mashed potatoes ahead of time?

Yes, mash them and keep warm in a covered pot over low heat or reheat gently with a splash of milk.

What can I substitute for sour cream in the potatoes?

Greek yogurt or heavy cream can be used for a similar creamy texture.