Every month Curtis Stone, the host of Bravo’s Top Chef Masters, takes a long ingredient, like citrus, as the throughline for a nine-course prix fixe menu. The result is a deft exploration that’s equal parts pastoral and plush. Even a salad with nasturtium petals and buttermilk dressing has resonance, while dishes like the hot carrot-and-orange soup with smoked parsnip cream reveal a knack for quiet complexity.