Preheat the oven to 400°F (200°C).

In a bowl, whisk together the Dijon mustard and maple syrup until well combined.

Coat the chicken breasts in the maple-dijon mixture and let marinate for a few minutes.

Spread the diced sweet potatoes on a baking sheet, drizzle with olive oil, and sprinkle with salt and pepper. Toss well.

Roast the sweet potatoes for 25-30 minutes until tender and golden brown.

In a skillet over medium heat, cook the chicken breasts for about 6-7 minutes per side or until fully cooked.

In a serving bowl, layer the cooked quinoa, fresh spinach, cooked chicken, and roasted sweet potatoes.