Preheat your oven to 425°F (220°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Pat the chicken thighs dry with a paper towel to ensure the surface gets a beautiful golden-brown sear during roasting.
In a small bowl, whisk together the olive oil, minced garlic, chopped rosemary, thyme, sea salt, and black pepper.
Place the chicken thighs, broccolini florets, and sliced red bell peppers onto the prepared baking sheet in a single layer.
Drizzle the herb oil mixture over the chicken and vegetables, tossing well to ensure every piece is evenly coated.
Roast for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the vegetables are tender.
Remove from the oven and squeeze the fresh lemon juice over everything to brighten the flavors before serving.