Pat chicken breasts dry with paper towels. If thickness varies significantly, gently pound to create uniform thickness of approximately 3/4 inch.

In a mixing bowl, combine olive oil, juice of one lemon (approximately 3 tablespoons), zest of one lemon (approximately 1 tablespoon), minced garlic, chopped rosemary, thyme leaves, salt, black pepper, and red pepper flakes if using. Whisk thoroughly.

Place chicken in a shallow dish or resealable bag. Pour marinade over chicken, ensuring all surfaces are coated. Create several small shallow slits in the thickest parts of the breast. Marinate for 30 minutes at room temperature or up to 4 hours refrigerated.

Position a rack in the middle of the oven and preheat to 425°F (218°C).

Heat an oven-safe skillet over medium-high heat. Add 1 tablespoon of olive oil.

Remove chicken from marinade, allowing excess to drip off but preserving any garlic and herb pieces attached to the surface. Place chicken presentation-side down in the hot skillet. Sear for 3-4 minutes until golden brown.

Flip chicken, reduce heat to medium, and add butter to the pan. Cut the remaining lemon into 1/4-inch slices and arrange around the chicken. Cook for 2 additional minutes, occasionally spooning the melted butter over the chicken.

Place the skillet in the preheated oven and bake for 5 minutes. Reduce oven temperature to 375°F (190°C) and continue baking for 10-15 minutes until internal temperature reaches 163°F (73°C).

Remove from oven (internal temperature will rise to 165°F/74°C during resting). Transfer chicken to a cutting board and let rest for 5-7 minutes. Slice against the grain and serve with pan juices drizzled over top.