Preheat the Oven: Set your oven to 425°F (220°C) to prepare for baking.
Make the Marinade: In a small bowl, whisk together the olive oil, juice of one lemon, minced garlic, chopped rosemary, dried oregano, sea salt, and freshly cracked black pepper until well combined.
Marinate the Chicken: Place the chicken breasts in a large resealable plastic bag or a shallow dish. Pour the marinade over the chicken, ensuring each piece is generously coated. Seal the bag or cover the dish and refrigerate for at least 30 minutes, or up to 2 hours for a more robust flavor infusion.
Prepare the Vegetables: On a large sheet pan, arrange the halved cherry tomatoes, sliced bell pepper, and red onion in an even layer. Drizzle with a little olive oil and season with sea salt and freshly cracked black pepper. Toss the vegetables to ensure they are evenly coated.
Combine Chicken and Vegetables: Once marinated, remove the chicken from the bag and arrange it on the sheet pan with the prepared vegetables. Top each chicken breast with a few lemon slices for an extra burst of flavor.
Bake to Perfection: Place the sheet pan in the preheated oven and bake for 20-25 minutes, or until the chicken is cooked through, reaching an internal temperature of 165°F (75°C), and boasts a lovely golden brown color. The vegetables should be fork-tender and slightly caramelized.
Rest and Garnish: Carefully remove the sheet pan from the oven and let the dish rest for 5 minutes to allow the juices to redistribute. If desired, garnish with fresh rosemary sprigs for an aromatic touch.
Notes
Serve with crusty bread or over rice for a complete meal.