Zucchini Squash Gratin Recipe

Zucchini Gratin Casserole Side Dish

Got a lot of zucchini? This is an awesome side dish recipe to use up a few yellow squash and zucchini from the garden.

This zucchini gratin has a great texture and flavor. It is a like a healthy comfort food and would be a nice side dish all year round, but definitely when summer squash is in season.

First, you want to cook down a bunch of sliced onion. Use about 1 pound of onion, which is usually about 1 1/2 medium yellow onions. Peel off the outer layer, cut each in half, then slice them up.

If you find yourself slicing zucchini and squash a lot, then you really should get yourself a mandoline slicer. The slices are all about the same thickness and you can get it done fast! It only takes a minute or two to slice up all 4 of the squash for this recipe! Very handy, especially for a recipe like this one.

You will need to use a large skillet or saute pan, 12-inches or larger, for all of the onion, zucchini, and yellow squash in there. If you have one with a lid, even better because you will need to cover the pan for part of the cooking time.

Just dump the tender zucchini, onion, and sauce into a smallish baking dish and top with the grated cheese and bread crumbs. I usually use freshly grated Parmesan with the Italian bread crumbs. So good!

To make this TERRAfit-friendly, use whole grain flour and whole grain bread crumbs.

This recipe is from Our Best Bites and Ina Garten.

A good mandoline can quickly, uniformly, and safely slice and julienne vegetables and fruits. It can also shred cabbage and neatly dice potatoes, tomatoes, and onions.

I just got a Swissmar Borner mandoline for myself because it has a ton of great ratings. I used it for this recipe and so far, so good! I also ordered some cut resistant gloves.

Zucchini Squash Gratin Recipe

Got a lot of zucchini? This is an awesome side dish recipe to use up a few yellow squash and zucchini from the garden.

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Prep Time: 10 minutes

Cook Time: 1 hour

Total Time: 1 hour 10 minutes

Serves: 6

Adjust Servings: 6

US CustomaryMetric

Ingredients

• 5 tablespoons butter
• 1 pound yellow onions cut in 1/2 and sliced
• 2 pounds zucchini and/or yellow squash sliced 1/4-inch thick (about 4)
• ¾ teaspoon kosher salt use 1/2 teaspoon if using table salt
• 1 teaspoon black pepper
• ¼ teaspoon ground nutmeg
• 2 cloves garlic finely minced or pressed
• 2 tablespoons all-purpose flour
• 1 cup milk
• 6 tablespoons Italian style bread crumbs
• ¾ cup grated Parmesan or Gruyere
• olive oil

Instructions

• Preheat the oven to 400°F/200°C
• Melt the butter in a large saute pan and cook the onions over low heat for 20 minutes, or until tender but not browned.
• As the onions are cooking, stir them occasionally and work on prepping the other ingredients.
• Add the zucchini and cook, covered, for 8-10 minutes, or until tender.
• Add the salt, pepper, and nutmeg and garlic and cook uncovered for 5 more minutes, stirring often.
• Whisk flour into the milk and add to pan, turning up heat slightly just until milk heats and starts bubbling.
• Then cook over low heat for a few minutes, until it thickens and makes a sauce.
• Pour the zucchini mixture, and all the sauce into an 8 by 10-inch baking dish (or something close to that).
• Combine the bread crumbs and Parmesan in a small bowl.
• Sprinkle on top of the zucchini mixture.
• Drizzle a little olive oil over the top (place your finger over the opening of the bottle to make it easier to just drizzle a little) and bake for 20 minutes, or until bubbly and browned. Cool for a few minutes before serving.

Recipe Notes

If doubling recipe, use a 9×13 (or similar) pan.

Nutrition

Calories: 268kcal | Carbohydrates: 24g | Protein: 11g | Fat: 16g | Sodium: 732mg | Fiber: 3g | Sugar: 10g