This yellow squash casserole recipe is a cheesy and delicious way to enjoy the summer squash that goes crazy every summer! It’s made with basic ingredients (only 5!) and takes just a few minutes to prep. Simply roast the squash, make the homemade cheese sauce, and then bake the cheesy squash casserole. Easy! And, this healthy keto summer squash casserole is naturally low carb. If you like healthy squash casserole recipes like this one, but have a pile of green zucchini to use, you can make this same recipe with zucchini instead, or try zucchini gratin. Or if you have more yellow squash to use up, try stuffed summer squash boats, or replace zucchini with yellow squash in my recipes for roasted zucchini, zucchini roll ups, or keto zucchini bread. These two types of summer squash are interchangeable in almost any recipe.

What Is Baked Yellow Squash Casserole?

This low carb summer squash casserole recipe is made up of layers of roasted yellow squash and then topped with a homemade cheese sauce and baked together until bubbly golden brown.

Summer Squash Casserole Ingredients

This section explains how to choose the best ingredients for yellow squash casserole, what each one does in the recipe, and substitution options. For measurements, see the recipe card below.

Summer squash – I used yellow squash, but you can also use zucchini!Olive oil – Use an extra virgin olive oil.Shredded cheese – I used cheddar, but any cheese you like will work. Try Swiss, Gruyere, or other keto cheeses.Heavy cream – This makes a rich, thick cheese sauce. Don’t replace it with half and half or other keto milks, as the sauce will be too runny. If you’re sensitive to dairy milk (but cheese is okay), you can swap the cream with full-fat coconut milk.Garlic – Use fresh or jarred garlic, either will work fine. Sea salt & black pepper

How To Make Squash Casserole

This section shows how to cook squash casserole with step-by-step photos and details about the technique, to help you visualize it. For full instructions, including amounts and temperatures, see the recipe card below.

Roast squash. Slice yellow squash into 1/4 inch slices and season with olive oil, sea salt, and black pepper. Roast for 10-12 minutes.

Make cheese sauce. In a saucepan, combine cheddar cheese, heavy cream, garlic, sea salt, and black pepper. Heat until melted and smooth.

Assemble. Layer roasted squash in baking dish. Pour sauce over squash and sprinkle remaining cheddar cheese on top. Bake. Bake the keto squash casserole until it starts to bubble, then broil for a few minutes until golden.

What do you do with an abundance of yellow squash?

You make the best yellow squash casserole, of course! This casserole is delicious, but it’s also a great way to use up some of the squash that’s going crazy in your garden.

Why is my squash casserole watery?

Because squash is made up of a lot of water, it will release a lot of water while it’s cooked. This is why we’re roasting the squash ahead of time, so that the water can release and it won’t make your yellow squash casserole watery.

Is yellow squash casserole keto?

Yes, this healthy baked yellow squash casserole is keto and low carb. The full nutrition stats can be found below the recipe card, but each serving has just 3.4 grams net carbs.

Storage Instructions

Store leftover yellow squash casserole in the refrigerator for 3-4 days.

Can you freeze squash casserole?

Yes, you can freeze the casserole for 2-3 months. Let it thaw in the fridge, then stir well before reheating. You may need to stir it again after reheating, as the sauce texture can change.

Reheating instructions:

Reheat the casserole in a 350 degree F oven for best results.

What Goes With Squash Casserole?

Healthy yellow squash casserole recipes like this one just need a main dish! Here are some ideas:

Pan Seared Chicken BreastStuffed Pork ChopsSugar-Free Glazed Keto HamGrilled Shrimp SkewersAir Fryer Chicken LegsAir Fryer Pork ChopsFilet Mignon

You can also make easy squash casserole recipes with other types of squash, such as buffalo chicken spaghetti squash casserole or zucchini casserole. Share your recipe picture by tagging @wholesomeyum and hashtag it #wholesomeyum on Instagram, or in our Facebook support group, too – I’d love to see it!