Prep the chicken and potatoes: Pat the chicken breasts dry with paper towels (drying the surface promotes better browning). Season both sides with 1 1/2 teaspoons kosher salt, 1/2 teaspoon black pepper and the smoked paprika. Cut the potatoes into even 1-inch cubes so they cook uniformly—uneven pieces give you mushy and undercooked bites.

Bring the potatoes to a simmer: Place the cubed potatoes in a pot, cover with cold water by 1 inch, add a large pinch of salt, and bring to a gentle boil over high heat. Starting potatoes in cold water cooks them more evenly through the center; boiling from hot water makes the exterior overcook before the inside is tender. Cook until a knife slides through easily, about 12–15 minutes.

Make the Greek yogurt chimichurri while the potatoes cook: In a bowl combine the Greek yogurt, lemon juice, Dijon, 1 tablespoon olive oil, chopped parsley, 1 smashed garlic clove (minced), a pinch of salt and the optional crushed red pepper. Whisk until smooth. This sauce adds protein and acidity to cut through the richness; the yogurt provides creamy tang and extra protein without heavy cream.

Sear the chicken for color and flavor: Heat a large ovenproof skillet over medium-high heat. Add 2 tablespoons olive oil and once shimmering, add the chicken breasts (do not overcrowd). Sear without moving for 3–4 minutes until a deep golden-brown crust forms—this Maillard reaction creates concentrated savory flavor. Flip, add the butter, another smashed garlic clove and the chopped rosemary/thyme; spoon the melted butter and herbs over the chicken for 1–2 minutes to baste and infuse flavor.

Finish in the oven: Transfer the skillet to a 400°F (200°C) oven and roast for 8–12 minutes, until the thickest part of the breast reaches 155–160°F (68–71°C). Removing a few degrees shy of 165°F ensures the chicken rests to a perfect 165°F while staying juicy. Rest the chicken for 6–8 minutes tented in foil before slicing to allow juices to redistribute.

Drain and dry the potatoes: Once tender, drain the potatoes and return to the hot pot for 1 minute to evaporate surface moisture—excess water makes whipped potatoes gluey. Add the butter, warm milk, remaining smashed garlic clove (finely minced), grated Parmesan, 1/2 teaspoon kosher salt and a pinch of pepper.

Whip the potatoes for silkiness: Use a potato ricer or hand masher for a rustic texture; for the silkiest finish, beat briefly with an electric hand mixer on low. Whipping releases starch—too much whipping makes them gummy, so go low and stop when smooth and fluffy. Taste and adjust seasoning. Stir in chopped chives for brightness.

Slice and plate: Slice the rested chicken breasts across the grain into 1/2-inch slices to maximize tenderness. Spoon a generous mound of garlic-whipped potatoes on each plate, fan the chicken slices over the potatoes, and finish with a generous drizzle of Greek yogurt chimichurri and a sprinkle of parsley or extra Parmesan.

Finish and serve: Serve immediately while the chicken is warm and the potatoes are fluffy. The cool, tangy yogurt sauce contrasts with the hot, savory chicken and the creamy potatoes—this contrast is what makes the dish feel elevated.