Preheat the oven to 400°F (200°C).
Toss the diced beets and sweet potatoes with olive oil, salt, and pepper.
Spread them out in a single layer and roast for 25-30 minutes, or until tender, stirring halfway through.
Combine the mixed greens and diced avocado in a large mixing bowl.
Add the roasted vegetables to the bowl once they’ve cooled slightly.
Whisk together olive oil, balsamic vinegar, honey, minced garlic, salt, and pepper in a small bowl.
Drizzle the dressing over the salad and toss gently to combine.
Serve immediately and enjoy!