Butternut Squash au Gratin

This Butternut Squash au Gratin is definitely worth trying; we've enjoyed it as warmed up leftovers as well as on the first evening.

1-1/2 tablespoons butter
olive oil
2 or 3 fresh onions, diced
3 tablespoons chopped fresh sage
salt and freshly ground black pepper to taste
about 2-1/2 to 3 pounds butternut squash - peeled, seeded, and cut into 1/2-inch cubes
2 cloves garlic, minced
3/4 teaspoon salt
1 1/4 cup whole milk
1 cup fresh bread crumbs 
1 1/2 cup Cheddar cheese, grated

Grease a gratin baking dish with butter.

Place a steamer insert into a saucepan and fill with water to just below the bottom of the steamer. Bring water to a boil. Add squash, cover, and steam until tender, about 20 minutes. 

Heat a few tablespoons of the olive oil in a large skillet over low heat. Add the chopped onions and sage. Cover and cook, stirring occasionally, until onions are translucent, about 25 minutes. Season with salt and black pepper. Add the garlic and the butter. Once the butter is melted, turn off the heat.  The garlic doesn’t need to be well-cooked. Pour the onion mixture over the bread crumbs and stir it all together.

Transfer squash to the gratin dish. Toss with the salt and pepper. Warm the milk over a low heat and pour it over the squash and stir gently.  Sprinkle the bread crumb mixture over the top and gently combine it into the squash while leaving the bulk of it on top. 

Bake in the preheated oven at 350° until gratin is bubbling and breadcrumbs are browned, 20 to 25 minutes. Sprinkle the grated cheese over the top and turn on the broiler.  Put it under the broiler for 5 minutes and serve!