Swiss Chard, Potato & Sweet Potato Gratin

The past few weeks have been a wonderful stroll down memory lane. There was lunch with high school friends, some of who I only get to see about once a year, and we caught up on each other's lives and reminisced about the past. The week before that, I visited my university roommate in Hamilton and we had a lazy weekend enjoying each other's company. It's moments like these that makes me wonder where time has gone and when exactly it was that we entered adulthood.





It was during this leisurely Sunday morning spent lounging on the couch, watching the Food Network that inspired me to make a gratin. My love for potatoes (I will eat them mashed, baked, roasted, deep friend and any other way you can cook a potato) and melted, gooey cheese made baking a gratin a no brainer, but I wanted something a little different from a tradition potato gratin.



I found this recipe on Smitten Kitchen and I knew it would not disappoint, as all the recipes I've tried from Deb have come out delicious. I decided to use both white and sweet potatoes; the starchiness combined with the bubbling gruyere made this meal warm and comforting.

Swiss Chard, Potato & Sweet Potato Gratin
Slightly adapted from Deb via Smitten Kitchen

While I used a combination of white and sweet potatoes, next time, I think I'll follow the intended result because golly, I do love me some sweet potatoes.

1/4 cup butter
1 small onion, finely chopped
1 large bunch Swiss chard, leaves and stems separated and both cut into 1-inch pieces
Pinch of nutmeg
2 cups whole milk
2 garlic cloves, minced
2 tablespoons flour
2 pounds potatoes and sweet potatoes, peeled and cut into 1/8-inch thick rounds
1 tablespoon dried thyme
Fine sea salt
Freshly ground black pepper
1 1/4 cups coarsely grated Gruyére cheese

Prep greens: Cook onion in 2 tablespoons butter in a wide 8-quart heavy pot over moderately low heat, stirring, until softened. Add chard stems, pinch of nutmeg, and salt and pepper to taste and cook, stirring, until vegetables are tender but not browned, about 8 minutes. Increase heat to moderately high and add chard leaves by large handfuls, stirring, until all greens are wilted. Season with salt and pepper then transfer greens to a colander to drain well and press out liquid with back of a large spoon.

Make sauce: Combine milk and garlic in small saucepan; bring to simmer; keep warm. Melt two tablespoons butter in a medium heavy saucepan over moderate heat and stir in flour. Cook roux, whisking, one minute, then slowly whisk in warm milk and boil, whisking, one minute. Season sauce with salt and pepper.

Assemble gratin: Preheat oven to 400°F. Butter deep 9×13 baking dish. Spread half of potatoes and sweet potatoes in the prepared baking dish. Sprinkle with salt, pepper, a quarter of the herbs and a 1/4 cup of the cheese. Distribute half of the greens mixture over the cheese, then sprinkle salt, pepper, a quarter of the herbs and 1/4 cup of the cheese over it. Pour half of bechamel sauce over the first two layers then continue with the remaining potatoes and sweet potatoes, more salt, pepper, herbs and cheese and then the remaining greens, salt, pepper and herbs. Pour the remaining sauce over the top of the gratin, pressing the vegetables slightly to ensure that they are as submerged as possible. Sprinkle with the last 1/4 cup of cheese.

Bake gratin for about 1 hour until golden and bubbly, and most of the liquid is absorbed. Let stand 10 minutes before serving.