Zucchini Gratin

  • Author: Nicole Gaffney (
  • Prep Time: 10
  • Cook Time: 40
  • Total Time: 50



  • 4 tablespoons unsalted butter, divided
  • 1/2 lb yellow onions (about 2 medium) cut in half and sliced
  • 1 lb zucchini (2 medium or 1 extra large), sliced 1/4 inch thick
  • 1 teaspoon salt
  • 1/2 teaspoon freshly ground black pepper
  • 1/8 teaspoon freshly grated nutmeg
  • 2 tablespoons flour
  • 1/2 cup whole milk
  • 3/4 cup panko or fresh bread crumbs
  • 3/4 cup grated Gruyere cheese
  • 1/4 cup minced fresh chives, optional


  1. Preheat the oven to 400 degrees. Butter a small, shallow baking dish (mine is 7″x10″) and set aside.
  2. Melt 3 tablespoons butter in a large saute pan over medium heat and begin to sweat out the onions. Cook for about 6-8 minutes, stirring occasionally, until they are softened, but not browned. Add the zucchini, toss around, then cover and cook for about 8 minutes until softened. Add the salt, pepper, nutmeg and flour, then mix to evenly distribute the flour. Add the milk and continue cooking until the mixture has thickened.
  3. Pour the zucchini mixture into the prepared baking dish. Combine the breadcrumbs with the Gruyere cheese and sprinkle over the mixture, then dot the remaining tablespoon of butter evenly over the top. Bake for about 20 minutes, until the top is golden brown and bubbling.
  4. Sprinkle chopped chives over the top to garnish, if desired. Allow to cool at least 10 minutes before serving.


  • Serving Size: 6