I grew up eating squash casseroles every summer, and this cheesy summer squash casserole brings back those cozy, homey memories with every bite.
It’s creamy, cheesy, and full of tender squash baked to bubbly perfection.
Whether it’s a casual dinner or a family cookout, this dish always disappears fast from the table.
Why I Love This Recipe
Comfort food at its best with fresh summer squash
Easy prep with pantry staples
Creamy, cheesy, and baked until golden
Great for family meals, potlucks, or even brunch
Can be prepped ahead and baked when ready
What You’ll Need (Ingredient Highlights)
Summer squash – Light, tender, and perfect for absorbing flavor
Onion – Adds sweetness and depth
Ro*Tel tomatoes – Brings color and a little zip
Cheddar cheese – Melty and rich; save some for the topping
Sour cream + mayonnaise – Creamy base that holds everything together
Salt & pepper – Just enough seasoning to bring it all to life
Pro Tips Before You Start
Drain the squash mixture well to avoid sogginess
Use mild Ro*Tel if you want a gentler flavor
Grate your own cheese for best melt and flavor
Let it rest before serving so it sets nicely
Add herbs like thyme or parsley for extra aroma
How to Make Cheesy Summer Squash Casserole
Step 1: Sauté the Vegetables
Preheat oven to 350°F. In a large skillet, heat olive oil over medium heat.
Add sliced squash and diced onion, and sauté for 8–10 minutes, stirring occasionally until tender.
Drain off any excess liquid.
Step 2: Mix the Casserole Filling
In a large bowl, combine the cooked squash mixture with drained Ro*Tel, sour cream, mayonnaise, salt, pepper, and 1 cup of cheddar (reserve the rest for topping).
Stir until everything is evenly coated.
Step 3: Assemble and Bake
Transfer the mixture into a medium-sized casserole dish.
Sprinkle the remaining cheese evenly over the top.
Step 4: Bake Until Bubbly
Bake for 20–30 minutes until the casserole is hot and the cheese is fully melted.
Let it rest for 5–10 minutes before serving.
What to Serve It With
Grilled chicken or pork chops
Crispy fried chicken
A green salad with vinaigrette
Fresh biscuits or cornbread
Sweet tea or iced lemonade
Variations / Substitutions
Add cooked bacon or ham for a smoky kick
Swap Ro*Tel for plain diced tomatoes if preferred
Use Greek yogurt in place of sour cream for a lighter twist
Add breadcrumbs or crushed crackers for a crunchy topping
Try mozzarella or Monterey Jack for a different cheese flavor
Storage & Leftovers
Store leftovers in an airtight container in the fridge for up to 4 days
Reheat in the microwave or oven until hot and bubbly
Avoid freezing – the texture can get watery
Use leftovers as a side for sandwiches or wraps
Add fresh herbs after reheating for a fresh touch
FAQs
Can I use yellow squash instead of zucchini?
Absolutely, yellow squash works just as well here.
Should I peel the squash?
No need—leave the skins on for texture and nutrients.
Can I prepare this casserole ahead of time?
Yes, you can assemble it and refrigerate it, then bake just before serving.
Is it spicy with Ro*Tel?
It can be slightly zesty—use the mild version if you prefer less heat.
Can I add breadcrumbs on top?
Yes! A sprinkle of buttery breadcrumbs or crushed crackers adds a lovely crunch.
What’s a good substitute for mayonnaise?
Greek yogurt or sour cream can replace some or all of the mayo.
Can I double the recipe for a crowd?
Definitely—just use a larger baking dish and adjust baking time as needed.
Final Thoughts
This cheesy summer squash casserole is simple, nostalgic, and deeply satisfying.
It’s the kind of dish that makes vegetables exciting and comforting at the same time.
Whether you’re feeding a crowd or just your family, this casserole brings that homemade love to the table.
