Preheat oven to 190C. (Top & bottom heat, no fan-force)
Mix rosemary, oregano, garlic, worcestershire sauce, and oil together in a large mixing bowl.
Add chicken, onion, and potatoes into bowl.
Toss to coat.
Lay everything out onto a large baking dish.
You can rest the chicken on top of the potatoes.
Season with salt and pepper.
Bake on middle rack for an hour, uncovered.
Serve with lemon wedges and garnish with chopped cilantro.