Grandmother's classic casserole gets an update with the simple addition of slivered fennel. This mild, licorice-flavored bulb, also sometimes known as anise, adds pleasing flavor and texture to creamy, melt-in-your-mouth potatoes, and breathes new life into an otherwise plain side dish. Serve this alongside your holiday ham or roast -- all your guests will love it, including your grandmother.
Preheat oven to 400° F. Peel potatoes and slice into 1/8 inch slices using a mandolin or very sharp knife. Divide into three piles and set aside. Chop off the frilly tops of the fennel bulb and save for another use. Slice off the root end of the bulb and discard, and then thinly cut the fennel into 1/4 inch slices. Peel onion, cut off root end and discard, then cut onion into 1/4 inch slices.
In a medium bowl, whisk together cream, broth, flour, pepper, nutmeg and garlic.
In a greased, 2-quart casserole dish, layer one portion of the potatoes. Top with a half of the fennel and onions. Add another layer of potatoes. Season lightly with salt and pepper. Pour in half of the cream mixture.
Layer on the rest of the fennel and onions and top with the remaining potato slices. Season lightly with salt and pepper and pour over the remaining cream mixture, pressing down to temporarily immerse the top layer. Drizzle the top with melted butter, place on a baking sheet with sides (in case it bubbles over) and put in the oven to bake for one hour, or until potatoes are golden brown on the top and tender when pierced with a knife.