3-Cheese Potato Gratin

I apologize that the picture is not more appealing.  Our daughter and grandson was over for dinner last night and the picture was an after thought.  But let me tell you this potato gratin is not an after thought.  It was delicious.  Gary loves scalloped potatoes and he liked these but his favorite is scalloped. I love cheese so gratin is my favorite. I got this recipe from Giada and as usual this will be a keeper for me. It's hard to see in this picture but there are sweet potatoes as well as Yukon gold potatoes in this recipe. 

Butter a baking dish.

2 tablespoons olive oil
1 large onion, chopped
2 cloves garlic, minced
1/3 cup heavy cream
1/4 cup chicken broth
1 teaspoon fresh rosemary
1 teaspoon salt
3/4 teaspoon pepper
5 Yukon Gold potatoes, peeled and cut 1/8 inch thick
1 large red skin sweet potato, cut 1/8 inch thick
1 1/2 cup grated gryere
1 1/2 cup Asiago
1/2 cup Pecorino Romano
2 tablespoons flat leaf parsley

Heat oven to 400 degrees.
 
Heat oil in skillet over medium heat.  Add onions and cook until tender and golden.  Add garlic and stir one minute.  Add cream broth, rosemary, salt and pepper. Cook about one minute and remove from heat.

Grate and mix all the cheese together in a bowl.
Put yams and potatoes together in a bowl.

Arrange 1/3 of the potato mixture in the bottom of a prepared baking dish.  Sprinkle with 1/3 of the cheese mixture.  Repeat twice more ending with layer of cheese mixture.  Pour the cream mixture over the layers and cover the pan with foil.

Bake the gratin until the potatoes are almost tender, about 45 minutes.  Remove the foil and continue to bake until the potatoes are tender and golden on top, 20-25 minutes longer.  Remove from oven and let the gratin rest 10 minutes.  Sprinkle with fresh parsley and serve.
6-8 servings