Bring a large pot of salted water to a boil. Add the spinach and cook for 2 minutes. Drain in a fine-mesh strainer, pressing with a large spoon to release as much water as possible. Finely chop and set aside.

Melt the butter in medium-heavy saucepan over medium-high heat. Add the shallots and cook, stirring, until soft, about 2 minutes. Add the garlic and flour and cook, stirring constantly with a heavy wooden spoon, until a light blond roux forms, 2 to 3 minutes. Add the milk in a steady stream, whisking constantly, and cook until thick and smooth, 1 to 2 minutes. Whisk in the cream and add the salt, white pepper and nutmeg and simmer until thickened, 3 to 5 minutes. Add the Pernod. Add the spinach, mix well and then fold in the Swiss and ¼ cup of the Parmesan cheese. Taste and adjust the seasoning if necessary.  

Serve immediately or transfer to a heavy-bottomed grill-proof baking dish for tailgating and let cool, then refrigerate until ready to tailgate. 

When you are ready to serve your tailgating guests, remove the spinach from the refrigerator and allow to come to room temperature for about 30 minutes. Preheat a grill to medium-low, about 400 degrees F. 

Place the baking dish on the grill and cook until the spinach is heated through and bubbly, usually about 30 minutes. Serve hot.

Note: Though originally developed for tailgating, this recipe may be prepared as instructed and then baked indoors in a regular oven at 400 degrees; timing may vary slightly.