• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer

Sprinkles and Sprouts

Great food with grocery store ingredients

  • Recipe Index
  • About
  • Contact Me
  • Nav Social Menu

    • Facebook
    • Instagram
    • Pinterest
    • RSS
Home > Holidays and Events > Thanksgiving > Sweet Onion Casserole with Crispy Topping

Sweet Onion Casserole with Crispy Topping

Updated: Mar 17th 2019 • Published: Nov 6th 2018 • 2 Comments

Jump to recipe button JUMP TO RECIPE
JUMP TO VIDEO
overhead view of the whole casserole with text at the top
a spoonful of casserole being lifted up with text at the top
Corner of the casserole dish on a pale table with text at the top

This Sweet Onion Casserole with Crispy Topping is a unique make ahead side dish. Onion is so overlooked as a vegetable, often it just added to dishes rather than being the star of the dish. This easy Thanksgiving side takes onions and turns them into the BEST kind of dish. One that is packed wth flavor and goes with everything!

a spoonful of onion casserole with the crispy breadcrumb topping being lifted out of a casserole dish

Everyone always has onions in the pantry or refrigerator, yet they are so often relegated to being chopped and added to other dishes. I do it myself, so many mid-week meals start with a chopped onion. And for good reason, onions add so much flavor to dishes.

So why not use that flavor and make it the shining star in a dish. And that is exactly what this Sweet Onion Casserole does. It takes thinly sliced onions and cooks them slowly in butter (or olive oil for vegans) and turns them into a melting sweet mass of deliciousness.

Top that with some crispy breadcrumbs and the dish is complete. Perfect for serving with roast turkey, roast beef, glazed ham or something rich like duck or goose.

So you know that means this Sweet Onion Casserole with Crispy Topping is just PERFECT for the holidays!

Go on pin it now and make it this Thanksgiving!

overhead view showing the crispy topping of the onion casserole

Jump Menu

  • How to make Onion casserole
  • What do you make the crispy topping out of?
  • Which onions to use for onion casserole?
  • Can I make this Onion Casserole ahead of time?
  • For more amazing Thanksgiving Side dishes check out this list of over 20 delicious ideas
  • Sweet Onion Casserole with Crispy Topping

How to make Onion casserole

Onion casserole is sweet onions slices cooked slowly in butter until meltingly tender and then topped with a delicious crispy topping.

You will need to slice the onions thinly for this dish. This is what creates the magic. The onions melt and meld together to make an almost creamy dish without any cream!

The quickest and easiest way to do this is to use a slicer attachment on your food processor. You can also use a mandolin but please for the love of sam use the finger guard! Those blades are lethal! Obviously you can go old school and use a sharp knife. It is possible, but far more time consuming.

sliced onions in a white shallow cast iron pan on a grey table

What do you make the crispy topping out of?

Many people use ritz crackers for the topping, but I find they can overpower the sweet flavor of the onions. Instead breadcrumbs are fried in olive oil, until crisp and then added to the casserole. This adds a great crunch but still allows the meltingly tender onions to shine.

And that is the point of this dish, to celebrate the sweet onion!

Which onions to use for onion casserole?

All onions are not created equal, so the onion you pick can really make a difference to the dish.

I know this is a sweet onion casserole, but you don’t want to use a sweet onion like Vidalias. They don’t have enough flavor. The best onions for this dish are you basic yellow onions or brown onions. They have great flavor and get nice and sweet when cooked slowly, they also hold their shape well so your casserole doesn’t end up as onion mush. Plus they have the added bonus of being the cheapest onion. And with the cost of holiday food always good to have a delicious budget friendly side!

the edge of the onion casserole in a white dish on a pale table.

Can I make this Onion Casserole ahead of time?

You sure can!

Like so many of my holiday sides, these can be made ahead and then just reheated whilst the meat is resting.

You can either heat these in the oven or just heat in the microwave and then finish in the oven.

To make ahead, cook the onions as directed. Then once you have transferred them to the casserole dish, cover tightly and refrigerate for up to 24 hours.

The breadcrumbs can be crisped up to a week in advance and then just kept in an airtight jar or ziplock bag.

Then come your big day you just assemble the casserole and bake for 30 minutes until hot and bubbly! Or heat the onions in the microwave, then top with the breadcrumbs and finish in the oven for 5 minutes.

The edge of the onion casserole with a metal spoon being stuck in

Why not pin this recipe for Sweet Onion Casserole with Crispy Topping Pin it here.

Enjoy x

For more amazing Thanksgiving Side dishes check out this list of over 20 delicious ideas

RECIPE NEWSLETTER

Signup and get my FREE soup cookbook.

By clicking submit, you acknowledge that the information you provide will be processed in accordance with our Privacy Policy and Terms of Service.

Sq image showing a big spoonful of onion casserole being scooped out of a white dish with blue napkin in the background
Print Recipe
3.5 from 8 votes

Sweet Onion Casserole with Crispy Topping

This Sweet Onion Casserole with Crispy Breadcrumbs Topping is a unique make ahead side dish. Onion is so overlooked as a vegetable, often it just added to dishes rather than being the star of the dish. This easy Thanksgiving side dish takes onions and turns them into the BEST kind of casserole – one that is packed wth flavor and goes with everything!
Prep Time10 mins
Cook Time55 mins
Total Time1 hr 5 mins
Course: Side
Cuisine: Modern Australian
Servings: 6 -8
Calories: 277kcal
Author: Claire | Sprinkles and Sprouts
For more great recipes follow me on PinterestFollow @sprinklessprout
Need Metric Measurements?Use the options below to toggle between cups and grams (if relevant)

Ingredients

US Customary – Grams
  • 2.5 lb onions
  • 1 stick butter
  • 1/2 tsp salt
  • 3/4 cup water
  • 2 tsp sugar
  • 2 tsp balsamic vinegar
  • 1 cup panko breadcrumbs
  • 1 tbsp olive oil
  • 1 tsp chopped chives
  • 1 tsp chopped parsley

Instructions

  • If cooking and serving immediately pre-heat the oven to 350ºF/175ºC
  • Peel and finely slice the onions. (see note 1)
  • Heat the butter in a large dutch oven or high sided skillet.
  • When it has just melted add in the onions and salt then stir to coat everything in the butter.
  • Cook, uncovered over a low heat for 30 minutes until the onions are soft but not coloured.
  • Turn up the heat and add the water, sugar and balsamic vinegar.
  • Let the mixture bubble gently for 10-15 minutes until the liquid has evaporated and the onions are melting tender.
  • Transfer the onions to a casserole dish and either continue to the next step or keep refrigerated for up to 24 hours. (see below for more prepare ahead instructions)
  • heat the olive oil in a non-stick skillet and add in the breadcrumbs, cook over a medium heat until the breadcrumbs start to color. Remove the pan from the heat and immediately tip the crumbs into a cold bowl. This stops the breadcrumbs from burning.
  • Sprinkle the breadcrumbs over the hot onions and cook for 10 minutes to allow everything to meld together.
  • Sprinkle over the fresh herbs and serve.

To prepare ahead.

  • Cook the onions up to the stage where you place them in the casserole. Then cover tightly and refrigerate for up to 24 hours.
  • Prepare the breadcrumbs and store in an airtight container or ziplock bag for up to 5 days.

To re-heat.

  • Place the onions in the oven and cook for 20 minutes until hot, sprinkle over the breadcrumbs and cook for a further 10 minutes.
  • Alternatively reheat the inions in the microwave (around 7 minutes) and then cover with the breadcrumbs and bake for 10 minutes.
  • Sprinkle over the fresh herbs and serve.

Notes

  1. The quickest and easiest way to slice the onions is to use a slicer attachment on your food processor. You can also use a mandolin but please for the love of sam use the finger guard! Those blades are lethal! Obviously you can go old school and use a sharp knife. It is possible, but far more time consuming.

Nutrition

Calories: 277kcal | Carbohydrates: 26g | Protein: 3g | Fat: 18g | Saturated Fat: 10g | Cholesterol: 40mg | Sodium: 411mg | Potassium: 295mg | Fiber: 3g | Sugar: 10g | Vitamin A: 470IU | Vitamin C: 14mg | Calcium: 66mg | Iron: 0.9mg
Tried this recipe?Mention @sprinklesandsprouts or tag #sprinklesandsprouts

If you love food why not subscribe to my newsletter, I will drop you an email every now and then, just to say hi and send you a couple of recipes I think you might love, like this Sweet Onion Casserole with Crispy Topping.

It isn’t everyday! I am not that organised. Usually it is once a week (ish). And as a thank you I will send you my soup cookbook FREE. Full of my fav soups!

Subscribe today 🙂
book_ad


RECIPE NEWSLETTER

Signup and get my FREE soup cookbook.

By clicking submit, you acknowledge that the information you provide will be processed in accordance with our Privacy Policy and Terms of Service.

Jump to recipe buttonFacebook share iconPinterest share icon

Filed Under: All Recipes, Sides, Thanksgiving

Reader Interactions

Comments

  1. JS says

    Dec 8th 2019 at 9:08 pm

    4 stars
    This is a great side dish! I substituted half the water with sherry wine which enhanced the flavor.

    Reply
    • Claire McEwen says

      Apr 30th 2020 at 5:15 am

      Love the addition of sherry!
      Cx

      Reply

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Primary Sidebar

Hi, I’m Claire,

Claire | Sprinkles and Sprouts

I believe cooking for those you love should be stress free and simple.

Here on Sprinkles and Sprouts you will find delicious meals all made with easy to find grocery store ingredients. Family friendly mains, sensational sides and delicious desserts. Plus a great selection of party food and appetizers.

Read More

RECIPE NEWSLETTER

Signup and get my FREE soup cookbook.

By clicking submit, you acknowledge that the information you provide will be processed in accordance with our Privacy Policy and Terms of Service.

Readers’ Favorites

Small close up of pasta in chicken broth braised celery in an oval white dish
a silver spoon dipping into a white bowl of hallandaise sauce tube pasta with a creamy steak sauce in a grey bowl
homemade flour tortilla on a sheet of baking paper close up on a chicken portion coated in peri peri seasonings
a small bowl of red salsa on a blue table close up on a sliced chicken breast with garlic spaghetti
small white bowl filled with linguine topped with shaved black truffle Beef and broccoli takeout style in a white bowl

Footer

All content, recipes and photographs are copyrighted to Claire McEwen and are the property of Sprinkles and Sprouts.
THEY MAY NOT BE REPUBLISHED IN PART OR WHOLE WITHOUT PERMISSION AND PROPER CREDIT.
Contact me to see republishing and syndication rights.

2014-2020 Sprinkles and Sprouts

  • Home
  • About Sprinkles and Sprouts
  • Recipe Index
  • Contact Me
  • Disclosure and Privacy Policy

Copyright © 2021 · Cravings Pro Theme on Genesis Framework · WordPress · Log in