Preheat the oven to 425°F (220°C) and prepare the sheet pan by lining it with parchment paper or lightly greasing it with olive oil.

In a small bowl, whisk together white miso paste, soy sauce (or tamari for a gluten-free option), honey or maple syrup, rice vinegar, sesame oil, minced garlic, and freshly grated ginger. For a subtle touch of heat, add crushed red pepper flakes. Whisk until smooth and fully combined. Taste the marinade before using it to ensure the balance of salty, sweet, and umami flavors is just right. Adjust the honey or soy sauce according to your preference.

Place the chicken thighs in a large bowl or a resealable zip-top bag. Pour half of the miso marinade over the chicken, ensuring each piece is coated evenly. For maximum flavor, use your hands or a spoon to massage the marinade into the chicken. Let the chicken marinate for at least 15 minutes at room temperature, which is perfect if you’re preparing the meal in a hurry. For deeper flavor, you can marinate the chicken for up to 2 hours in the refrigerator.

While the chicken is marinating, work on the sweet potatoes. Peel them if desired, then cut them into 1-inch cubes for even roasting. In a separate bowl, toss the sweet potato cubes with olive oil, salt, and pepper. Make sure each cube is evenly coated to ensure they roast properly and develop a golden, caramelized surface. Spread the sweet potatoes evenly on the prepared sheet pan, leaving space for the chicken. Proper spacing allows air to circulate, which is key to achieving perfectly roasted sweet potatoes.

Once the chicken has marinated, arrange the thighs on the sheet pan alongside the sweet potatoes. Drizzle the remaining miso marinade over both the chicken and the sweet potatoes to add extra depth of flavor. Try to place the chicken in the center or slightly separated from the sweet potatoes so that each component cooks evenly and absorbs maximum flavor.

Roast for 25-30 minutes, or until the chicken reaches an internal temperature of 165°F (74°C) and the sweet potatoes are tender and caramelized on the edges. Halfway through roasting, give the sweet potatoes a gentle stir to ensure even browning. This step helps bring out the natural sweetness of the potatoes while keeping the chicken juicy and perfectly cooked.

Once cooked, remove the sheet pan from the oven and allow the chicken to rest for 5 minutes. Resting helps the juices redistribute, keeping the chicken tender and moist. Sprinkle with freshly sliced green onions and sesame seeds for a burst of color, flavor, and texture.

Serve and enjoy.