Preheat the oven to 400°. Spread half of the fennel in a 9-by-13-inch glass or ceramic baking dish. Pour the wine over the fennel, then sprinkle half of the <em>panko</em> on top. Repeat with the remaining fennel and <em>panko</em>. Cover and bake for 20 minutes, then remove the foil and bake for 10 minutes longer, until the topping is browned and crisp. Serve hot.