Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper.
Dice the potato into 1/2-inch cubes and slice the zucchini into 1/2-inch thick half-moons.
Cut the chicken breast into uniform 1-inch pieces to ensure even cooking.
In a large mixing bowl, combine the chicken, potatoes, and zucchini with olive oil, sea salt, black pepper, garlic powder, and oregano.
Toss the ingredients thoroughly until every piece is well-coated in the oil and spices.
Spread the mixture in a single layer on the baking sheet, making sure not to overcrowd the pan so the vegetables can crisp properly.
Roast for 25 to 30 minutes, flipping the ingredients halfway through, until the potatoes are golden and the chicken is cooked through.
Remove from the oven and drizzle with fresh lemon juice before serving warm.