New York Strip Steak in a Mushroom Sauce

Toss carrots with a large drizzle of oil on a baking sheet. Season with salt and pepper. Roast in oven under tender and slightly charred at edges, 20-25 minutes. Meanwhile, place potatoes in a medium pot with enough salted water to cover by 1 inch. Bring to a boil. Cook until tender, about 15 minutes, then thoroughly drain.

Heat a large drizzle of oil in a medium pan over medium-high heat (use a nonstick pan if you have one). Add onion and cook, stirring occasionally, until browned and very soft, about 15 minutes. Add a splash of water every now and then, scraping up any browned bits on bottom. Transfer to a small bowl. Season with salt and pepper.

Return drained potatoes to empty pot. Place over low heat. Mash with a potato masher until smooth. Stir in sour cream. Season with salt and pepper. Keep over low heat. Wipe out pan used for onion, then heat a large drizzle of oil in it over medium-high heat. Pat steak dry with a paper towel and season with salt and pepper. Add to pan and cook to desired doneness, 3-6 minutes per side.

Remove steak from pan; set aside. Add 2 TBSP butter and mushrooms to same pan over medium-high heat. Cook, tossing, until softened, 2-4 minutes. Toss in garlic and cook until fragrant, about 1 minute. Stir in demi-glace and ¼ cup water, then bring to a boil. Lower heat and reduce to a simmer. Stir in 1 tsp mustard (we sent more). Simmer until slightly thickened, 1-2 minutes. Remove from heat. Stir in half the parsley.