Butternut Squash Gratin with Onions and Sage

1/4 c. olive oil
4 c. thinly sliced onion
4 thyme sprigs
2 T fresh chopped sage, or 2 t dried
Salt and freshly milled pepper
6 c. peeled butternut squash, cut into 1/2 in. cubes
1/2 c. flour
2 T chopped parsley
1/2 c. grated Gruyere or fontina cheese
1/2 c. plus 2 T heated whole milk
1 c. fresh bread crumbs

Directions

Preheat the oven to 350 degrees. Lightly oil or butter a 2-quart gratin dish.

Heat half the oil in a skillet over medium heat. Add the onion, thyme and sage, and cook, stirring frequently, until the onions are lightly caramelized, about 15 minutes. Season with 1/2 teaspoon salt and pepper to taste. Spread in the gratin dish, return the skillet to medium heat, and add the remaining oil.

Toss the squash in the flour, letting the excess fall away. Add the squash to the pan and cook until it begins to brown in places on both sides, about 7 minutes. Add the parsley, season with salt and plenty of pepper, and cook for 1 minute more. Layer the squash over the onions, cover with the cheese, then add the milk. Cover and bake for 25 minutes, then uncover, add the bread crumbs, and bake until the top is browned and the liquid absorbed, about 25 minutes more.

From Deborah Madison's book Vegetarian Cooking For Everyone.