Move over, scalloped potatoes. There is a new casserole in town and it is stealing the whole show. These Southern Scalloped Onions are sweet onions sliced into rounds, tossed with herbs and a little cayenne, bathed in cream and baked under a blanket of gooey, golden gouda. Low and slow in the oven, the onions turn meltingly soft and jammy, and honestly, people will be fighting over the crispy corner bits.

If you have ever thought of onions as a supporting actor, this recipe is here to change your mind. It takes about 15 minutes of hands-on time, then the oven does the rest. That makes it a dream side dish for Thanksgiving, holiday dinners or a Sunday roast, when your stovetop is already a war zone. Put this next to roast chicken, turkey or a good steak and watch it disappear.

Why You’ll Love These Southern Scalloped Onions

• Shockingly easy. Slice, season, pour, sprinkle, bake. No roux, no sauce to babysit, no fuss.
• Sweet, savoury and cheesy. Sweet onions mellow beautifully in the oven, the gouda brings a nutty richness and the cayenne adds a gentle warmth.
• Oven does the work. Once it is in the oven, you are free to make the rest of dinner (or pour yourself something nice).
• Budget friendly. Onions are one of the most affordable vegetables out there, and this dish makes them taste like a million bucks.
• A holiday table showstopper. It is different enough to get people talking, but cozy and familiar enough that everyone goes back for seconds.

Ingredients

• 3 ½ lbs sweet onions (like Vidalia), sliced into ¼-inch rounds
• 2 teaspoons fresh thyme leaves
• 1 ½ teaspoon dried oregano leaves
• 1 teaspoon dried mustard powder
• 1 ½ teaspoon onion powder
• ½ teaspoon salt
• ½ teaspoon cayenne pepper
• ½ cup heavy cream
• 2 cups grated gouda

Serves 8 as a side dish

Tips for the Best Southern Scalloped Onions

• Use sweet onions. Vidalia, Walla Walla or any sweet onion will give you that mellow, almost caramel-like flavour. Regular yellow onions are much sharper.
• Slice evenly. Aim for ¼-inch rounds so everything cooks at the same rate. A mandoline makes quick work of it (watch your fingers).
• Break them into rings. Separating the onions into rings as you toss them helps the seasoning coat every piece and lets them settle into an even layer.
• Grate your own gouda. Pre-shredded cheese is coated with anti-caking agents that keep it from melting as smoothly. Grating a block takes 2 minutes and is worth it.
• Do not skip the covered bake. The foil traps the steam, so the onions soften completely before the top gets a chance to brown.
• Let it rest. Give it 10 minutes out of the oven so the creamy juices settle and thicken slightly before serving.

How to Make Southern Scalloped Onions

1. Get ready. Preheat oven to 375°F and butter a 13×9-inch casserole dish.
2. Season the onions. Add the onions to a large bowl. Sprinkle over the thyme, oregano, mustard powder, onion powder, salt and cayenne and toss to coat. Break the onions into rings as you mix them.
3. Fill the dish. Pour the onions into a 13×9-inch casserole dish, lay them flat over the bottom.
4. Add the cream and cheese. Pour the heavy cream over top of the onions. Scatter the gouda evenly over the top.
5. Bake covered, then uncovered. Cover with aluminum foil and bake for about 45 minutes, until the onions are soft and tender. Remove the aluminum foil and bake for another 35 minutes until the top is golden brown.

More Cozy Side Dishes for Your Table

Building a holiday menu? These sides play very nicely together:

• Scalloped Turnips au Gratin: another creamy, scalloped side that turns a humble vegetable into a star
• Sour Cream and Onion Potato Gratin: for the onion lovers who still want their potatoes
• Potato Dauphinoise: the classic French gratin, rich and silky
• Root Vegetable Gratin: a cozy mix of root veg baked until bubbling
• Green Bean Bundles with Prosciutto: a fresh, pretty green side to balance all that cheese
• Sweet and Sticky Roasted Butternut Squash: a holiday table favourite

External Resources

• National Onion Association: everything you ever wanted to know about onion varieties, storage and handling
• USDA FoodKeeper: guidance on safely storing leftovers and dairy

Frequently Asked Questions

What are scalloped onions? Scalloped onions are sliced onions baked in cream, usually with cheese, until they are soft, sweet and bubbling. Think scalloped potatoes, but with onions as the star.

What kind of onions are best for scalloped onions? Sweet onions like Vidalia or Walla Walla are best. They have less sulphur and more natural sugar, so they bake up mellow and sweet instead of sharp.

Can I make Southern Scalloped Onions ahead of time? Yes. Assemble the dish, cover and refrigerate for up to 1 day. Let it sit on the counter for 30 minutes before baking, and add a few extra minutes to the covered bake if it is still cold in the centre.

Can I use a different cheese instead of gouda? Sure. Gruyère, white cheddar or fontina all melt beautifully. Smoked gouda is also delicious if you want a little smoky flavour.

What do you serve with scalloped onions? They are perfect alongside roast turkey, roast chicken, pork tenderloin, ham or a good steak. They are a natural fit for Thanksgiving and holiday dinners.

Can I make this less spicy? Yes. The cayenne adds a gentle warmth, but you can reduce it to a pinch or leave it out entirely if you are cooking for spice-shy eaters.

How do I store and reheat leftover scalloped onions? Store leftovers in an airtight container in the fridge for up to 3 days. Reheat in a 350°F oven until bubbling, or in the microwave in a pinch.

Southern Scalloped Onions

Print Recipe

5 Stars 4 Stars 3 Stars 2 Stars 1 Star

No reviews

Southern Scalloped Onions: sweet Vidalia onions seasoned with herbs and a touch of cayenne, baked in cream under golden gouda. An easy, oven-does-the-work side dish.

• Author: Andrea Buckett
• Prep Time: 15 minutes
• Cook Time: 1 hour 20 minutes
• Total Time: 1 hour 35 minutes
• Yield: 8 servings

Ingredients

Units USM

• 3 1/2 lbs sweet onions (like Vidalia), sliced into 1/4-inch rounds
• 2 teaspoons fresh thyme leaves
• 1 1/2 teaspoon dried oregano leaves
• 1 teaspoon dried mustard powder
• 1 1/2 teaspoon onion powder
• 1/2 teaspoon salt
• 1/2 teaspoon cayenne pepper
• 1/2 cup heavy cream
• 2 cups grated gouda

Instructions

1. Preheat oven to 375°F and butter a 13×9-inch casserole dish.
2. Add the onions to a large bowl. Sprinkle over the thyme, oregano, mustard powder, onion powder, salt and cayenne and toss to coat. Break the onions into rings as you mix them.
3. Pour the onions into a 13×9-inch casserole dish, lay them flat over the bottom.
4. Pour the heavy cream over top of the onions. Scatter the gouda evenly over the top.
5. Cover with aluminum foil and bake for about 45 minutes, until the onions are soft and tender. Remove the aluminum foil and bake for another 35 minutes until the top is golden brown.

Notes

• Sweet onions are key. Use Vidalia, Walla Walla or another sweet onion for the best flavour.
• Slice evenly. Aim for ¼-inch rounds so the onions cook at the same rate.
• Cheese swaps. Gruyère, white cheddar, fontina or smoked gouda all work well.
• Make ahead. Assemble up to 1 day ahead, cover and refrigerate. Add a few minutes to the covered bake.
• Storage. Refrigerate leftovers for up to 3 days. Reheat in a 350°F oven until bubbling.