Cut the potatoes into halves. Drizzle with olive oil, and season with salt, pepper and Provencal herbs. Toss to coat.
Place in a baking dish and roast in the oven at 200°C for 20-25 minutes until tender and golden brown.
Cut the cherry tomatoes in half and set aside.
Chop the garlic, olives, and sun-dried tomatoes.
Cut the chicken breast fillets into bite-size pieces.
Heat olive oil in a skillet over medium heat. Add the garlic and chicken and cook until brown but not cooked through. Stir in the olives and sun-dried tomatoes and cook until the chicken is fully cooked. Season with salt and pepper.
Remove the potatoes from the oven. Add the chicken on top of the potatoes and top with the cherry tomatoes. Season with salt and pepper.
In a small bowl, combine the breadcrumbs and pumpkin seeds. Sprinkle with the tomatoes and return to the oven. Bake for a further 10 minutes or until the tomatoes are softened and the panko mixture is crispy.