|Unfortunately my photography skills does not do this dish justice|
adapted from Michael Symon's Heartland Thanksgiving Menu Food & Wine November 2011
1 pounds Swiss chard, large stems discarded
1 tablespoons olive oil
2 leeks, white and tender green parts only, sliced 1/4 inch thick
1 garlic cloves, minced
2 tablespoons unsalted butter
5 Tbsp all-purpose flour
1 1/3 cups whole milk
3 Tbsp shredded Gruyère cheese
3 Tbsp freshly grated Parmesan cheese
Pinch of teaspoon freshly grated nutmeg
Salt & Freshly ground black pepper
Blanch the chard in batches until wilted,in a large pot of boiling water. Drain, squeeze dry and chop.
Heat the oil in a pot. Add the leeks and a pinch of salt. Cover and cook over moderately low heat, stirring, until tender. Uncover, add the garlic and cook, stirring, until fragrant, then add the chard, Season with salt to taste and remove from the heat.
Preheat the oven to 425°. Coat a baking dish with cooking spray. In a saucepan, melt the butter. Stir in the flour over moderate heat to form a paste. Gradually whisk in the milk about 1/3 at a time allowing the mixture to cook and thicken in between additional. Bring the sauce to a boil, whisking constantly. Reduce the heat to low and cook, whisking often, until thickened and no floury taste remains, 15 minutes. Whisk in the cheeses and the nutmeg; season with salt and pepper to taste. Mix the sauce into the leeks and chard. Season with salt and pepper.
Transfer the mixture to the prepared baking dish. Bake in the upper third of the oven for about 25 minutes, until bubbling and golden brown on top. Let rest for at least 10 minutes before serving.