Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Peel and cube the sweet potato into 1/2-inch pieces, slice the zucchini into rounds, and chop the bell pepper into bite-sized strips.
In a large bowl, toss the sweet potato, broccoli, bell pepper, and zucchini with 0.5 tbsp of olive oil, half of the sea salt, half of the black pepper, and all of the dried oregano.
Spread the vegetables in a single layer on the prepared baking sheet and roast for 20-25 minutes until the sweet potatoes are tender and the edges are slightly caramelized.
While the vegetables roast, season the chicken breast on both sides with garlic powder and the remaining sea salt and black pepper.
Heat the remaining 0.5 tbsp of olive oil in a heavy-bottomed skillet over medium-high heat.
Place the chicken in the skillet and sear for 6-7 minutes per side, or until the internal temperature reaches 165°F and the exterior is golden and crisp.
Remove the chicken from the pan and let it rest for 3 minutes before slicing.
Plate the roasted vegetables alongside the pan-seared chicken and serve immediately.