Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Pat the cubed chicken breast and the drained chickpeas very dry with paper towels to ensure they roast properly.
In a large mixing bowl, whisk together the olive oil, sea salt, black pepper, garlic powder, smoked paprika, and lemon zest.
Add the chicken cubes and chickpeas to the bowl, tossing thoroughly until every piece is evenly coated in the spice mixture.
Spread the mixture in a single layer on the prepared baking sheet, making sure the pieces are not crowded.
Bake for 20-25 minutes, tossing once halfway through, until the chicken is cooked through and the chickpeas are golden.
Place the fresh baby spinach into a serving bowl and top with the warm roasted chicken and chickpea mixture.
Drizzle the fresh lemon juice over the entire dish just before serving to brighten the savory flavors.