Adjust rack to top position (top and middle positions for 4 servings) and preheat oven to 425 degrees. Wash and dry 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, cut broccoli into bite-size pieces. 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 oil in a large pan over medium-high heat. Add wrapped chicken; sear until browned and crispy, 2-3 minutes per side (it’ll finish cooking in the next step).

Transfer to one side of a baking sheet. (For 4 servings, arrange chicken across entire sheet.) Reserve pan.

Toss broccoli on opposite side of sheet from chicken with a large drizzle of oil, salt, and pepper. (For 4 servings, toss broccoli on a second sheet; roast chicken on top rack and broccoli on middle rack.)

Roast on top rack until chicken is cooked through and broccoli is browned and tender, 15-18 minutes.

Remove sheet from oven. Carefully toss broccoli with lemon zest.

While chicken and broccoli roast, finely chop chives.

To pot with drained potatoes, add crema, half the chives, 2 TBSP butter (3 TBSP for 4 servings), and as much truffle seasoning 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 (⅓ 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) until melted. Season with salt and pepper.

Once cool enough to handle, slice chicken crosswise. Divide chicken, potatoes, and broccoli between plates. Top chicken with sauce and remaining chives. Serve.