Preheat your oven to 400°F and line a large rimmed sheet pan with parchment paper for easy cleanup.
Cut the chicken breast into 1-inch cubes and slice the baby potatoes into halves or quarters so they cook quickly.
Chop the red bell pepper into 1-inch pieces and break the broccoli into bite-sized florets.
In a large mixing bowl, whisk together the extra virgin olive oil, fresh lemon juice, dried oregano, garlic powder, sea salt, and black pepper.
Add the chicken, potatoes, peppers, and broccoli to the bowl and toss thoroughly until every piece is coated in the herb marinade.
Spread the mixture onto the prepared sheet pan in a single even layer, making sure not to crowd the ingredients so they roast instead of steam.
Bake for 20 to 25 minutes, or until the chicken is cooked through and the potatoes are tender and lightly browned.
Remove from the oven and garnish with fresh chopped parsley and an optional extra squeeze of lemon juice before serving.