The late author Nora Ephron had it right when she said that the ultimate comfort food is potatoes. In her case, it was mashed potatoes. For me, I’m a lover of potato casseroles. I find this variation on potatoes gratin my antidote to tough times and freezing weather. It’s a taste memory that never gets old.
This casserole features sliced potatoes layered with onion marmalade, finished with a garlicky cheese topping. You’ll often find potato recipes with raw onion, but here the onions are tamed into a sweet tangle of deliciousness. The way to make this Seriously Simple is to make up the onion marmalade ahead and then assemble when ready to bake.
There is nothing like the flavor of caramelized onions that have a rich, silky, savory-sweet flavor laced between the potatoes and cheese mixture. Watch the onions carefully so they are golden brown and don’t burn. The addition of sugar and balsamic balance out their flavor.
A mixture of garlic and parsley (feel free to add your favorite herbs here) is combined with nutty, grated Gruyere cheese and layered and topped on the potatoes. I like to use chicken or vegetable broth to give it moisture instead of cream for a lighter result.
This is easy to put together when you have the ingredients sliced and measured. You can use a sharp knife, a mandoline, or a food processor with the slicing blade to prepare the potatoes. Make sure the slicing blade is set at 1/4 inch so the casserole will cook at the suggested time. If the potatoes are thicker, know that you may need to bake the casserole for a few more minutes.
One thing you must do is to first cover the casserole with buttered aluminum foil to have the potatoes “steam” while they bake. If they are uncovered for the entire time, they will not cook properly. The final stage of baking is uncovered so that the cheesy topping can melt.
Serve this as a vegetarian dish (use vegetable broth) alongside a saute of green beans, snap peas, mushrooms, and broccoli. This dish is a welcome companion to simple grilled or roasted meats, chicken, or fish, as well as stews.
Caramelized Onion, Potato, and Cheese Casserole
Serves 6 to 8- 2 tablespoons olive oil
- 2 large onions, thinly sliced
- 1/2 teaspoon sugar
- 1 teaspoon balsamic vinegar
- Salt and freshly ground black pepper
- 4 pounds russet (baking) or Yukon Gold potatoes, scrubbed and sliced into 1/4-inch-thick slices
- 4 medium garlic cloves, minced
- 3 tablespoons finely chopped fresh parsley
- 2 cups grated Gruyere cheese
- 2 cups chicken or vegetable broth
- 2 tablespoons unsalted butter, cut into small pieces
Preheat the oven to 375 degrees F. Grease a 9-by-13-inch baking dish. In a small bowl, combine the garlic, parsley, cheese, and pepper to taste.
Layer half the potatoes in the bottom of the baking dish. Spread the onion mixture evenly over the potatoes. Season with salt and pepper. Sprinkle half of the cheese mixture evenly on top. Layer the remaining potatoes over the cheese and season with salt and pepper. Pour the chicken broth over the potatoes. Sprinkle the remaining garlic-cheese mixture evenly over the top and dot with the butter.
Cover the dish with buttered foil and bake for 30 minutes. Remove the foil and bake uncovered for 30 more minutes, or until the top is brown and crusty and the potatoes are fork tender. Serve immediately.
Advance preparation: This may be made up to four hours ahead, covered, and left at room temperature. Reheat in a 375-degree F oven for 20 minutes, or until bubbling.
