Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Peel and dice the sweet potato into 1-inch cubes, and slice the bell pepper into strips.
In a large bowl, toss the sweet potato, broccoli florets, and bell pepper with 0.5 tablespoon of olive oil, half of the sea salt, black pepper, garlic powder, and 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 lightly browned.
While the vegetables roast, season the chicken breast with the remaining sea salt, black pepper, garlic powder, and oregano.
Heat the remaining 0.5 tablespoon of olive oil in a cast-iron or stainless steel skillet over medium-high heat.
Place the chicken in the pan and sear for 5-7 minutes per side, or until the internal temperature reaches 165°F and the exterior is golden brown.
Remove the chicken from the pan and let it rest for 3-5 minutes before slicing.
Plate the sliced chicken alongside the roasted vegetables and serve immediately.