Summer Squash Au Gratin

By Irvin Lin

This au gratin side dish takes advantage of all the summer squash that you see at the grocery store and farmers market. The touch of fresh sage hints at the autumn season just around the corner. Try to find a nice crusty rustic bread to cube and use for the au gratin. The texture it lends to the dish is key!

  • Yield: Serves 6 people.
  • Course: Side Dish

All you need for this recipe and more...


  • 2 zucchinis
  • 2 yellow squash
  • 1 yellow onion
  • 4 garlic cloves, minced
  • 4 tablespoons olive oil, divided
  • 2 teaspoons kosher salt, divided
  • 1 1/2 teaspoon fresh ground black pepper, divided
  • 1/2 cup heavy cream
  • 1 tablespoon chopped fresh sage
  • 1 cup grated Parmesan cheese, divided
  • 4 cups of cubed crusty bread (about 8 slices)
  • 1 tablespoon Italian parsley


  1. Preheat the oven to 400˚F and grease an Anolon® Vesta 3-Quart Oval Au Gratin. Slice the zucchini, yellow squash and onions into 1/4-inch thick rings. 
  2. Drizzle 1 tablespoon of the olive oil into a large skillet that has a cover and heat on medium-high until it starts to shimmer. Add the onions and garlic and cook until the onions start to soften, about 5 minutes. Add the zucchini and yellow squash and cover, reducing the heat to medium low. Cook, stirring occasionally, until the squash starts to soften, about 10 to 12 minutes. Sprinkle 1 1/2 teaspoon of salt and 1 teaspoon of pepper over the vegetables halfway through the cooking.
  3. While the vegetables are cooking, toss the bread cubes with the parsley, remaining salt and pepper, olive oil and 1/2 of the Parmesan cheese until the bread cubes are well coated.
  4. Once the squash has started to soften, pour the cream over the vegetables, add the sage, 1/2 of the Parmesan cheese and 1 cup of the bread cubes. Stir to incorporate and heat the cream. Then pour all of the ingredients into the au gratin dish. Sprinkle the bread cubes over the top of the vegetables and bake in the oven for 20 to 25 minutes or until the cubes on top have started to brown.