Sirloin and Sherry Shallot Sauce

Lightly oil a baking sheet. In a large bowl, combine potatoes, 2 TBSP olive oil (4 TBSP for 4 servings), garlic powder, and a couple large pinches of salt and pepper; toss until potatoes are completely coated. Arrange potatoes on prepared sheet into clusters (about 6 slightly overlapping slices each). Roast on middle rack for 12 minutes.

Meanwhile, toss green beans on a second baking sheet with a drizzle of olive oil, salt, and pepper. Once potatoes have roasted 12 minutes, remove from oven and sprinkle with Parmesan. Return to middle rack and place green beans on top rack. Roast until potatoes are tender, cheese is lightly browned, and green beans are tender, 10-12 minutes.

While veggies 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 until browned, 3-6 minutes per side. Turn off heat; wipe out pan. Transfer steak to sheet with green beans; roast until cooked to desired doneness, 4-7 minutes. (If green beans finish first, remove from sheet and continue roasting steak.) Set aside to rest.

Heat a drizzle of oil in pan used for steak over medium heat. Add shallot and cook, stirring, until softened, 1-2 minutes. Pour in half the vinegar (use all for 4 servings). Simmer until reduced by half, 15-30 seconds. Stir in ¼ cup water (⅓ cup for 4) and stock concentrate. Simmer until thickened, 2-3 minutes. Turn off heat. Stir in sour cream and 1 TBSP butter (2 TBSP for 4). Season with salt and pepper.