Brussels Sprout Casserole

Name: Brussels Sprout Casserole with Ritz Crackers
Prep time: 10 min
Cook time: 1 h 10 min
Total time: 1 h 20 min
Yield: 5 servings
Cuisine: American
Ingredients: ½ cup chopped yellow onion; 4 tbsp (1/2 stick) salted butter; 1 (10.5 oz) can cream of mushroom soup; 2 large eggs; ½ cup mayonnaise; 5 cups quartered Brussels sprouts; 1 cup cheddar cheese, divided; 1 ½ cup crushed Ritz crackers

This creamy Brussels sprout casserole combines roasted onions, cream of mushroom soup, and mayonnaise in a rich base, topped with melted cheddar cheese and crushed Ritz crackers for a buttery, crunchy finish.

🌍American 🥗Vegetarian 🏷️Brussels sprouts 🏷️Casserole 🏷️Side dish 🏷️Suvie 10 ingredients or less

🏷️

Total

1h 20m

Servings

5

Difficulty

Medium

Est. Cost

$17–$28

Ingredients

½ cup chopped yellow onion
4 tbsp (1/2 stick) salted butter
1 (10.5 oz) can cream of mushroom soup
2 large eggs
½ cup mayonnaise
5 cups quartered Brussels sprouts
1 cup cheddar cheese, divided
1 ½ cup crushed Ritz crackers

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Instructions

1
Place ½ cup chopped onion and 4 tbsp butter in a Suvie pan. Place the pan in the bottom zone of your Suvie and roast at 400°F for 15 minutes.
2
Meanwhile, place 1 can cream of mushroom soup, 2 eggs, ½ cup mayonnaise, and ¼ teaspoon black pepper in a large bowl, and whisk until blended.
3
Once the onions have roasted, add them to the bowl along with any residual butter. Add 5 cups quartered Brussels sprouts and ½ cup of cheddar cheese to the bowl, and toss to combine.
4
Transfer the casserole mix to a Suvie pan (you can use the same pan used to roast the onions). (For Suvie 2.0 we recommend covering the pan with foil). Place the pan in the bottom zone of your Suvie, input settings, and cook now. Roast at 350°F for 50 minutes.
5
After the cook, remove the pan from your Suvie, and remove the foil. Top the casserole with the remaining ½ cup cheddar cheese and 1 ½ cups of crushed Ritz crackers. Return the pan to the bottom zone of your Suvie, uncovered, and roast at 350°F for 10 minutes or until the cracker crumbs are toasted and the cheese has melted.
6
After the cook, remove the pan from your Suvie, and set aside to rest for 5 minutes before serving. Season to taste with salt and pepper.

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Tips & Notes

Pro tips

Quarter Brussels sprouts evenly so they roast at the same rate; smaller pieces may dry out while larger ones stay firm.
Sauté the onions until golden and caramelized before mixing into the casserole—this adds depth and prevents raw onion flavor.
Crush Ritz crackers by hand into uneven chunks rather than fine crumbs; larger pieces stay crunchier during baking.
Reserve some cheddar cheese for the topping layer to ensure melted, golden cheese on top rather than only in the filling.

Substitutions

Crushed Ritz crackers → panko breadcrumbs mixed with melted butter (more neutral flavor, still crispy)
Mayonnaise → sour cream or Greek yogurt (slightly tangier, thinner consistency)
Cheddar cheese → Gruyère or Fontina (sharper, more sophisticated flavor)
Cream of mushroom soup → cream of celery or cream of chicken (lighter alternative)

Storage & make-ahead

Store covered in the refrigerator up to 4 days. Reheat at 350°F for 15–20 minutes until warmed through; cover with foil to prevent the topping from over-browning.

Common Questions

Can I make this casserole ahead of time?

Yes. Assemble the casserole (without the cracker topping), cover, and refrigerate up to 24 hours. Add the Ritz topping and bake just before serving to keep crackers crispy.

How do I know when the casserole is done baking?

Bake until the top is golden brown and the filling is bubbling around the edges, about 35–45 minutes at 350°F. The cheese should be melted and the crackers golden.