Prepare the dressing by mixing the olive oil, maple syrup, lemon juice, cumin, cayenne, salt, and pepper together. You can use a small bowl and a whisk, or place them in a jar, cover with a lid, and shake until it emulsifies.
Place the quinoa, black beans, corn, diced tomato, peppers, onion, avocado, and cilantro into a large bowl and pour the dressing on top. Mix well and serve.