Preheat your oven to 425°F (220°C) and line a large rimmed sheet pan with parchment paper for easy cleanup.
Pat the chicken breast completely dry with paper towels and cut it into uniform 1-inch bite-sized pieces.
In a large mixing bowl, combine the chicken pieces and the fresh broccoli florets.
Drizzle the extra virgin olive oil over the chicken and broccoli, then sprinkle with dried oregano, garlic powder, sea salt, and black pepper.
Toss the mixture thoroughly with your hands or tongs until every piece is evenly coated in the oil and seasonings.
Spread the chicken and broccoli onto the prepared sheet pan in a single layer, ensuring there is space between the pieces so they roast rather than steam.
Roast in the center of the oven for 18-22 minutes, tossing halfway through, until the chicken is golden and the broccoli edges are charred and crispy.
Remove from the oven and immediately toss with the fresh lemon zest and lemon juice to brighten the flavors before serving.