The combination of buttery Yukon gold and fluffy baking potatoes offers richness and a nice contrast both in flavor and texture. If you don't have a food mill, cream the potatoes and cooking liquid with a potato masher.
Fresh herbs, butter, and Dijon mustard provide big flavor in this simple roast chicken. It first cooks breast side down, then is turned over to finish cooking. This method ensures moist breast meat. Look for a bird labeled "roasting chicken" or "roaster"—these usually have more meat and are more tender than broiler-fryers.