Preheat oven to 400°F (200°C).
On a large rimmed baking sheet, toss cubed sweet potatoes with 1 tablespoon of olive oil, salt, and pepper.
Roast sweet potatoes for 20-25 minutes, flipping halfway through, until tender and lightly browned.
In a small mixing bowl, whisk together Dijon mustard, maple syrup, apple cider vinegar, and garlic powder until smooth.
Heat the remaining 1 tablespoon of olive oil in a large skillet over medium-high heat.
Add chicken cubes to the skillet and cook for 6-8 minutes, stirring occasionally, until chicken is browned and internal temperature reaches 165°F.
Reduce heat to low and pour the maple dijon sauce over the chicken, tossing to coat for 2 minutes until the sauce thickens.
Divide fresh baby spinach and roasted sweet potatoes among four bowls.
Top each bowl with the glazed chicken and garnish with chopped pecans.