Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Cut the chicken breast into bite-sized strips and peel and cube the sweet potato into 1/2-inch pieces.
In a mixing bowl, whisk together the olive oil, harissa paste, sea salt, and black pepper.
Add the chicken and sweet potatoes to the bowl, tossing thoroughly until every piece is evenly coated in the harissa mixture.
Spread the chicken and potatoes in a single layer on the prepared baking sheet and roast for 20-25 minutes until the potatoes are tender and the chicken is cooked through.
While the chicken roasts, slice the cucumber into thin rounds and place the baby spinach into a large serving bowl.
Assemble the bowl by topping the spinach with the roasted chicken and sweet potatoes, then add the sliced cucumbers.
Finish with a dollop of hummus in the center and a fresh squeeze of lemon juice over the entire bowl.