Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Chop the broccoli florets, red bell pepper, and zucchini into uniform bite-sized pieces and place them in a large mixing bowl.
Drizzle 0.5 tbsp of the extra virgin olive oil over the vegetables and toss with half of the sea salt, black pepper, and garlic powder until evenly coated.
Spread the vegetables in a single layer on the prepared baking sheet and roast for 18-20 minutes until tender and slightly caramelized at the edges.
While the vegetables are roasting, pat the chicken breast dry with a paper towel and season both sides with the remaining olive oil, sea salt, black pepper, garlic powder, and smoked paprika.
Heat a cast-iron skillet or heavy-bottomed pan over medium-high heat. Once hot, add the chicken and sear for 6-7 minutes per side until the exterior is golden brown and the internal temperature reaches 165°F.
Remove the chicken from the skillet and transfer it to a cutting board to rest for at least 5 minutes to lock in the juices.
Slice the chicken into strips and serve alongside the roasted vegetable medley, finishing the dish with a bright squeeze of fresh lemon juice.