Wow, it sure got chilly this week. Perfect weather for a side dish like a potato gratin. I am catering a surprise birthday party for an octogenarian tomorrow and this family wanted something warm, comforting and old fashioned for a side dish with beef. This recipe is not only easy, it's delicious. I think they are going to love this!
Caramelized Onion-Potato Gratin
1 yellow onion, thinly sliced
2 T good olive oil
1 T unsalted butter
2 lbs russet potatoes (4 large potatoes)
2 1/4 c heavy cream, separated
2 1/2 c grated Gruyère cheese (1/2 pound) (expensive but worth it)
1/2 c Asiago cheese
1 t kosher salt
1/2 t freshly ground black pepper
2 T fresh thyme, stripped off the stem
Preheat the oven to 350 degrees. Butter a 10-by-15-by-2-inch (10-cup) baking dish, set aside. Sauté the onions in the olive oil and butter on medium-low heat for 15 minutes, until browned lightly and caramelized. Peel the potatoes and thinly slice them by hand or with a mandoline (one of my favorite kitchen tools). Mix the sliced potatoes in a large bowl with 2 cups of cream, 2 cups of Gruyère, 1/4 c Asiago, salt, and pepper. Add the sautéed onion and mix well. Pour the potatoes into the baking dish. Press down to smooth the potatoes. Combine the remaining 1/4 cup of cream, the rest of the asiago and Gruyère and sprinkle on the top. Bake for 1 1/2 hours, until the potatoes are very tender and the top is browned and bubbly. Allow to set for 10 minutes and serve. Serves 10-12.
Note: Add thinly sliced Black Forest ham and a handful of frozen peas and you have a single dish casserole dinner.
Voted Best Caterer for Tuolumne and Calaveras Counties 2016