Preheat oven to 400°F (200°C) and line a large rimmed sheet pan with parchment paper or a silicone baking mat.
In a large mixing bowl, toss the cubed sweet potatoes with 1 tablespoon of olive oil, 1/2 teaspoon garlic powder, 1/2 teaspoon onion powder, salt, and pepper.
Spread the sweet potatoes in a single layer on the prepared sheet pan and roast for 15 minutes to give them a head start.
While the potatoes roast, combine the cubed chicken in the same mixing bowl with the remaining olive oil, buffalo sauce, and the remaining garlic and onion powders.
Remove the sheet pan from the oven, slide the sweet potatoes to one side, and place the chicken cubes on the other side of the pan.
Return the pan to the oven and roast for an additional 15 to 20 minutes, or until the chicken reaches an internal temperature of 165°F (74°C) and the potatoes are tender.
Garnish with sliced green onions and serve immediately or distribute into meal prep containers with optional ranch dressing or blue cheese crumbles.