Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Pat the chicken breast dry with a paper towel and cut it into 1-inch bite-sized cubes.
Rinse and drain the chickpeas, then roll them between two paper towels to ensure they are completely dry, which helps them crisp up in the oven.
In a large mixing bowl, combine the chicken cubes, chickpeas, and broccoli florets.
Drizzle the olive oil over the mixture and sprinkle with the ground cumin, smoked paprika, sea salt, and black pepper.
Toss everything thoroughly until the ingredients are evenly coated in the oil and spices.
Spread the mixture in a single, even layer on the prepared baking sheet, ensuring nothing is overcrowded.
Roast for 20 to 25 minutes, tossing the ingredients halfway through, until the chicken is cooked through and the chickpeas are golden brown.
Remove from the oven and immediately drizzle with fresh lemon juice to brighten the flavors before serving.