01 - Preheat the oven to 425°F. Line a baking sheet with parchment paper.
02 - In a large bowl, combine the olive oil, lemon juice, minced garlic, parsley, thyme, rosemary, salt, black pepper, and lemon zest. Whisk until well blended.
03 - Add the chicken breasts to the marinade and coat thoroughly on all sides. Allow to marinate for at least 10 minutes at room temperature, or cover and refrigerate for up to 4 hours for deeper flavor penetration.
04 - Toss the trimmed broccolini with olive oil, salt, black pepper, and lemon zest until evenly coated. Arrange in a single layer on the prepared baking sheet.
05 - Heat a large oven-safe skillet over medium-high heat. Remove the chicken from the marinade and sear for 2 to 3 minutes per side until lightly golden brown.
06 - Transfer the skillet with the seared chicken to the oven. Place the baking sheet with broccolini in the oven as well. Roast both for 15 to 18 minutes, until the chicken reaches an internal temperature of 165°F and the broccolini is tender with slightly crisp tips.
07 - Remove the chicken from the oven and let it rest for 5 minutes before slicing. Arrange on plates alongside the roasted broccolini. Garnish with extra chopped fresh herbs and lemon wedges. Serve immediately.