Preheat your oven to 400°F (200°C).
On a large rimmed baking sheet, toss the chopped bell peppers, sliced zucchini, and red onion with half of the olive oil, sea salt, and black pepper.
Spread the vegetables in a single layer and roast for 18-20 minutes until they are tender and show light golden charring.
While the vegetables are roasting, heat the remaining olive oil in a large non-stick skillet over medium-high heat.
Add the ground chicken to the skillet, breaking it apart with a wooden spoon, and cook until browned and no longer pink.
Stir in the minced garlic, dried oregano, and red pepper flakes, cooking for about 1 minute until the spices become fragrant.
Add the roasted vegetables directly into the skillet with the cooked chicken and toss to combine.
Drizzle the fresh lemon juice over the mixture, give it one final toss to brighten the flavors, and serve immediately.