• Adjust rack to top position (top and middle positions for 4 servings) and preheat oven to 425 degrees. Wash and dry all produce. • Dice potatoes into ½-inch pieces. Place in a medium pot with enough salted water to cover by 2 inches. Bring to a boil and cook until tender, 15-20 minutes. Reserve ½ cup potato cooking liquid; drain and return potatoes to pot. • Meanwhile, zest and halve lemon.

• Pat chicken* dry with paper towels; season all over with salt and pepper. • Lay two slices of prosciutto beside each other on a flat surface. Tightly roll prosciutto around chicken. Repeat with remaining prosciutto and chicken.

• Heat a drizzle of olive oil in a large pan over medium-high heat. Add wrapped chicken; sear until browned and crispy, 2-3 minutes per side. • Transfer to one side of a baking sheet. Roast on top rack for 5 minutes (you’ll add the green beans then). (For 4 servings, spread chicken out across entire sheet; roast on top rack until cooked through, 15-17 minutes.)

• Once chicken has roasted 5 minutes, remove sheet from oven. • Carefully toss green beans on empty side with a large drizzle of olive oil, lemon zest, and salt. (For 4 servings, leave chicken roasting and toss green beans on a second sheet; roast on middle rack.) • Return to top rack until chicken is cooked through and green beans are tender, 10-12 minutes. (If chicken is done first, remove from sheet and continue roasting beans.) • Once cool enough to handle, slice chicken crosswise.

• Meanwhile, finely chop chives. • To pot with drained potatoes, add sour cream, half the chives, 2 TBSP butter (3 TBSP for 4 servings), and as much truffle zest as you like. • Mash until smooth, adding splashes of reserved potato cooking liquid as needed. Season with salt and pepper.

• Heat pan used for chicken over medium-high heat. Add stock concentrate, ¼ cup water (1⁄3 cup for 4 servings), and lemon juice to taste. Cook until thickened, 2-3 minutes. Turn off heat; stir in 1 TBSP butter (2 TBSP for 4), salt, and pepper. • Divide chicken, potatoes, and green beans between plates. Top chicken with sauce and remaining chives.