Preheat your oven to 400°F.
Score the chicken breast lightly and season with salt and pepper on both sides.
In a small bowl, mix the peanut butter with a tiny splash of warm water to loosen it, then coat the chicken evenly.
Place the peanut-coated chicken on a lightly greased baking sheet. Drizzle a little olive oil over it.
Slice the sweet potato (if not already halved) into rounds or cubes, toss with a pinch of salt, pepper, and remaining olive oil, and spread on another baking tray.
Roast the chicken and sweet potatoes in the oven. Roast the chicken for about 18-20 minutes or until cooked through and the coating is crispy, and roast the sweet potatoes for about 25 minutes or until tender and lightly caramelized.
While the chicken is cooking, prepare the berry glaze by gently heating the mixed berries in a small saucepan over low heat, stirring occasionally until they soften and form a slight syrup, about 5 minutes.
Once done, plate the chicken alongside the roasted sweet potatoes, and drizzle the warm berry glaze over the chicken for a burst of tangy sweetness.
Serve immediately and enjoy the delightful contrast of crispy, nutty chicken and sweet, roasted potatoes with vibrant berry accents.