Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Chop the broccoli into bite-sized florets, slice the carrots into rounds, and dice the red bell pepper into one-inch pieces.
Place the vegetables on the prepared baking sheet and toss with 0.5 tablespoon of olive oil and half of the sea salt and black pepper.
Spread the vegetables in a single layer and roast for 18 to 20 minutes until they are tender and the edges are slightly charred.
While the vegetables roast, season the chicken breast on both sides with the garlic powder, dried oregano, and the remaining salt and pepper.
Heat the remaining 0.5 tablespoon of olive oil in a heavy-bottomed skillet or cast-iron pan over medium-high heat.
Add the chicken to the hot skillet and sear for 6 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 let it rest for 3 minutes to lock in the juices before slicing.
Plate the sliced chicken alongside the roasted vegetable medley and serve immediately while hot.