To prepare the rustic chicken with potatoes, begin by peeling the onion and garlic. If using a whole chicken, make sure it is thoroughly cleaned and free of any remaining pinfeathers, then pat it dry and cut it into pieces. Peel the potatoes and cut them into fairly large cubes.
Heat a generous drizzle of extra virgin olive oil in a large skillet. Add the onion cut into quarters, the garlic cloves, and the chicken pieces.
Add the rosemary, sage, bay leaves, and thyme.
Brown all the ingredients together over brisk medium-high heat for about 15 minutes. Pour in the white wine, let the alcohol evaporate, and season with salt.
Add the potatoes and continue cooking, partially covered with a lid, for about 10 minutes. Remove the lid and cook uncovered for another 15 minutes.
Turn the ingredients frequently to ensure even browning on all sides, adding a splash of hot water if needed, until everything is fully cooked and tender.
Serve the rustic chicken with potatoes piping hot, garnished with fresh rosemary.