Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper.
Rinse the chickpeas and pat them very dry with a clean kitchen towel to ensure they get crispy in the oven.
Cut the chicken breast into uniform 1-inch cubes and chop the broccoli and bell peppers into bite-sized pieces.
In a large mixing bowl, combine the chicken, chickpeas, broccoli, and peppers.
Drizzle with olive oil and sprinkle with sea salt, black pepper, garlic powder, and smoked paprika, tossing until everything is evenly coated.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the ingredients aren't overcrowded.
Roast for 20 to 25 minutes, tossing halfway through, until the chicken is cooked through and the chickpeas are golden and slightly crunchy.
Remove from the oven and drizzle with fresh lemon juice before serving warm.