Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
In a large bowl, toss the broccoli florets, sliced carrots, and chopped red bell pepper with 0.75 tablespoons of olive oil, half of the sea salt, and half of the garlic powder.
Spread the vegetables in a single layer on the prepared baking sheet and roast for 15 to 20 minutes until they are tender and the edges are slightly caramelized.
While the vegetables are roasting, season the chicken breast on both sides with the remaining sea salt, black pepper, garlic powder, and dried oregano.
Heat the remaining 0.75 tablespoons of olive oil in a heavy-bottomed skillet over medium-high heat until shimmering.
Place the chicken breast in the skillet and sear for 5 to 7 minutes per side, or until the exterior is golden brown and the internal temperature reaches 165°F.
Remove the chicken from the pan and allow it to rest on a cutting board for 5 minutes to keep the juices locked in.
Slice the chicken and serve alongside the roasted vegetables, drizzling everything with fresh lemon juice just before eating.