Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Dice the chicken breast into uniform 1-inch cubes and place them in a large mixing bowl.
Rinse and drain the chickpeas, then pat them thoroughly dry with a paper towel to ensure they become crispy during roasting.
Add the dried chickpeas, chopped red bell peppers, and sliced red onions to the bowl with the chicken.
Drizzle the olive oil and lemon juice over the mixture, then sprinkle with oregano, garlic powder, sea salt, and black pepper.
Toss all ingredients until the chicken and vegetables are evenly coated in the oil and spices.
Spread the mixture in a single layer on the prepared baking sheet, ensuring space between pieces for even browning.
Roast for 20 to 25 minutes, tossing halfway through, until the chicken is cooked through and the chickpeas are golden.
Remove from the oven and serve immediately while the vegetables are tender and the flavors are bright.