Cook quinoa per package instructions.
Preheat oven to 425.
Slice all veggies. Set cucumber aside. Coat onion and bell pepper in 1 tbsp avocado oil and 1 tsp each of the seasonings (garlic, oregano, harissa) and place on a sheet pan.
Roast onion and bell pepper in oven until tender (about 25-30 mins).
Coat a skillet in 1 tbsp avocado oil, add a chicken breast, and coat in 1 tsp each of the seasonings. Cook for about 7 minutes each side, until it has reached at least 165F.
Assemble bowl with quinoa, veggies, chicken, cucumber, and olives. Add salt and pepper to taste and drizzle with olive oil.
Additional toppings may include feta cheese, hummus, and/or fresh herbs such as dill.