• Adjust rack to top position and preheat oven to 450 degrees. Wash and dry produce. • Dice potatoes into 1/2-inch pieces. Halve and peel shallot; finely chop one half (save the rest for another use).

• Place potatoes in a medium pot with enough salted water to cover by 2 inches. Bring to a boil and cook until tender, 12-15 minutes. • Drain and return potatoes to pot; mash with 2 TBSP butter (4 TBSP for 4 servings) until smooth. Season generously with salt and pepper. • Keep covered off heat until ready to serve.

• Meanwhile, trim green beans if necessary. Toss on a baking sheet with a drizzle of olive oil, salt, and pepper. • Roast on top rack until green beans are tender, 10-12 minutes.

• While green beans roast, pat steak* dry with paper towels; season all over with salt and pepper. • Heat a large drizzle of oil in a large pan over medium-high heat. Add steak and cook to desired doneness, 5-7 minutes per side. • Turn off heat; transfer to a cutting board to rest. Wipe out pan.

• Heat a drizzle of oil in same pan over medium heat. Add chopped shallot; cook, stirring, until softened, 1-2 minutes. • Pour in half the vinegar (all for 4 servings). Simmer until reduced by half, 30 seconds. • Stir in stock concentrate and 1/4 cup water (1⁄3 cup for 4). Simmer until thickened, 2-3 minutes more. Turn off heat. • Stir in sour cream and 1 TBSP butter (2 TBSP for 4) until melted and combined. Season with salt and pepper.

• Slice steak against the grain. • Divide steak, mashed potatoes, and green beans between plates. Top steak with sauce and serve.