Southern Squash Casserole with Cheddar and Crackers

Why You’ll Love This Recipe

• Classic comfort: creamy, cheesy, and topped with a buttery, crisp cracker crust.
• Not watery: sautéing and draining the squash keeps the casserole velvety, not soggy.
• Effortless bake: everyday ingredients and simple steps, perfect for weeknights or potlucks.
• Versatile: easy to make gluten-free or spice it up with a few swaps.

Grocery List

• Produce: Yellow squash (2 lb), sweet onion (1 large), fresh chives or parsley (optional)
• Dairy: Unsalted butter, full-fat sour cream, sharp cheddar cheese
• Pantry: Buttery round crackers (1 sleeve), kosher salt, black pepper, garlic powder (optional), cayenne or paprika (optional), cooking spray or extra butter for greasing

Full Ingredients

For the Casserole

• 2 lb yellow summer squash (about 6–7 small), ends trimmed, sliced into 1/4-inch rounds
• 1 large sweet onion (Vidalia), thinly sliced (about 2 cups)
• 2 tbsp unsalted butter (for sautéing)
• 1 tsp kosher salt, divided (1/2 tsp for the veg, 1/2 tsp in the sauce)
• 1/2 tsp freshly ground black pepper
• 1/2 tsp garlic powder (optional)
• Pinch cayenne pepper, about 1/8 tsp (optional)
• 1 cup full-fat sour cream
• 1 1/2 cups shredded sharp cheddar cheese, divided (1 cup for the filling, 1/2 cup on top)

For the Buttery Cracker Topping

• 1 sleeve buttery round crackers (about 30 crackers; 1 1/2 cups lightly packed crumbs)
• 3 tbsp unsalted butter, melted
• 1/4 tsp smoked paprika (optional, for color)
• 1 tbsp chopped fresh chives or flat-leaf parsley, for garnish (optional)

Step-by-Step Instructions

Step 1: Preheat and prepare the dish

Preheat the oven to 350°F. Grease a 2-quart baking dish (an 8×8-inch, 9-inch square, or oval casserole) with butter or cooking spray. This size helps the casserole bake evenly and the topping get deeply golden.

Step 2: Slice and season the vegetables

Slice the squash into 1/4-inch rounds and thinly slice the sweet onion. Toss both with 1/2 teaspoon kosher salt in a large bowl and let sit for 5 minutes. This brief rest starts drawing out extra moisture so the casserole won’t be watery.

Step 3: Sauté to drive off moisture

Melt 2 tablespoons unsalted butter in a large skillet over medium heat. Add the onions and cook, stirring, for 2–3 minutes until just translucent. Add the squash and cook, stirring occasionally, until tender and most of the liquid has evaporated, 8–10 minutes. Transfer the mixture to a colander set over a bowl and let it drain and steam off for 3–5 minutes. Gently press with a spatula to release excess moisture.

Step 4: Make the creamy cheddar base

In a large bowl, whisk together the sour cream, 1 cup shredded sharp cheddar, remaining 1/2 teaspoon kosher salt, black pepper, and the optional garlic powder and cayenne. Fold in the drained squash and onion until evenly coated.

Step 5: Assemble the casserole

Spread the creamy squash mixture into the prepared baking dish. Sprinkle the remaining 1/2 cup cheddar evenly over the top. This cheese layer melts into the crumbs and helps the topping adhere.

Step 6: Add the buttery cracker topping

In a medium bowl, combine the crushed buttery crackers with the melted butter (and smoked paprika, if using) until the crumbs are evenly moistened. Scatter the crumbs in an even layer over the casserole, covering to the edges.

Step 7: Bake, rest, and serve

Bake at 350°F for 25–30 minutes, until the edges are bubbling and the topping is deep golden-brown. For extra color, broil for 45–60 seconds, watching closely. Let the casserole rest for 10 minutes to set slightly. Garnish with chopped chives or parsley and serve warm.

Pro Tips

• Uniform slices matter: 1/4-inch squash rounds cook evenly and hold their shape in the creamy sauce.
• Beat the water: Salt, sauté, then briefly drain the squash/onion mixture to keep the casserole silky, not soupy.
• Shred your own cheese: Freshly shredded sharp cheddar melts smoother than pre-shredded.
• Crumbs with texture: Crush crackers into a mix of fine crumbs and small pieces for maximum crunch.
• Use the right dish: A 2-quart dish gives the ideal filling-to-crust ratio and helps the top brown well.

Variations

• Gluten-Free: Use gluten-free buttery crackers for the topping; everything else stays the same.
• Spicy Kick: Add 1 finely chopped jalapeño to the sauté and substitute pepper jack for half the cheddar.
• Bacon & Scallion: Stir 4 slices crispy chopped bacon and 2 sliced scallions into the filling; top as directed.

Storage & Make-Ahead

Refrigerate leftovers, tightly covered, for up to 4 days. Reheat uncovered at 350°F for 15–20 minutes (or microwave in short bursts) until hot and the topping re-crisps. For make-ahead, assemble the casserole without the cracker topping, cover, and refrigerate up to 24 hours. Add the topping just before baking; increase bake time to 30–35 minutes if starting from cold. Freezing is not recommended—the squash can release water when thawed and affect texture.

Nutrition (per serving)

Approximate values for 8 servings: 300 calories; 22 g fat; 14 g carbohydrates; 9 g protein; 2 g fiber; 640 mg sodium.