How To Roast Onions So They’re Sweet, Soft & Creamy

Discover how to roast onions in a way that makes them soft and creamy and super-versatile.

As I reached into my dry goods cupboard for my bag of garlic, my hand scrubbed against a big mesh sack of Vidalia onions. “Hmmm,” I thought. “What if I roast some sweet onions the same way I was going to roast the garlic.”

A couple of hours later, my mind was swimming sweetly in onion-y inspirations

Two roasted onions in a metal bowl on a countertop.

What I discovered was this. When you trim the ends off a sweet onion, drizzle it with oil and seasoning, wrap it tightly in foil, and then roast it, the result is a creamy soft center so sweet that it can be eaten straight out of the foil or used in a hundred different ways.

How to Roast Onions So They’re Sweet, Soft, and Creamy

Step #1

Preheat the oven to 350ºF. Trim both ends off of a Vidalia onion and then set the onion on one of its cut ends on a piece of foil.

Vidalia onion on foil with ends cut off.

Step #2

Drizzle the onion with 1 teaspoon of olive oil and sprinkle with salt and pepper. Snuggle in a few sprigs of thyme if you have them (a good pinch of dried thyme leaves are fine here too).

Vidalia onion that has oil and fresh thyme sprigs on it.

Step #3

Wrap the onion tightly in foil and place it in a baking pan. Repeat with as many Vidalia onions as you’d like to roast.

Two onions wrapped in foil in a white baking pan.

Step #4

Roast for about 90 minutes, until a knife inserted into the center of the onion smooshes in very easily.

Foil wrapped onions partially unwrapped and being tested with a knife.

Step #5

Remove foil from the onions, but be careful – sometimes there is a bit of onion broth that has come out of the onions. Don’t spill it or discard it. It can be used to flavor dips, soups, sauces ,etc. Let the onions sit until they’re cool enough to touch.

Roasted onions in metal bowl.

Step #6

Remove and discard the skins from the onions. (Sometimes there is an additional layer of onion that got a bit dry as well. If this has happened, discard this dry outer layer too. A bit of browning around the edges is fine. It’s a tough, dry, difficult to mash layer that we want to avoid).

Roasted onions with skins removed in metal bowl.

Step #7

Discard the thyme and you’re ready to use your roasted onions in all sorts of delicious ways.

Uses For Roasted Onions:

-Toss soft onion petals with linguine and olive oil for an easy side dish

-Mash the roasted onions with butter, salt, and pepper and spread it onto grilled bread

-Add a purée of the roasted onions to gravy or chili

-Use the purée warm on its own as a (vegan-friendly!) gravy

-Smear it into mashed potatoes (add roasted garlic as well to really spoil yourself)

-Purée it and serve it as a dip for veggies

-Drizzle it with maple syrup and served it alongside grilled salmon

Those are some of my favorite ways that I’ve used these delicious roasted onions, but I’m sure there’s many, many more. Now that you know how to roast onions, will you add them to a dish or eat them as is?

If you love sweet Vidalia onions, you might also want to jump over and grab my baked bloomin’ onion recipe.

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How To Roast Onions


  • Author: Christine Pittman
  • Prep Time: 5 minutes
  • Cook Time: 90 minutes
  • Total Time: 1 hour 35 minutes
  • Yield: 4 servings
  • Category: Side Dish
  • Method: Baked
  • Cuisine: American

Description

Super easy but full of flavor. Roasting Vidalia onions the way you roast garlic yields a soft and smooth texture and lovely sweet and mild onion flavor. The instructions here are for one onion but you can do 2 or 3 at a time (last time, I used 6!).


Ingredients

  • 1 medium Vidalia onion, with peel on
  • 1 tsp. olive oil
  • 1/4 tsp. coarse salt
  • 1/4 tsp. coarse black pepper
  • 2 sprigs of fresh thyme (or 1/2 tsp dried thyme leaves)

Instructions

  1. Preheat the oven to 350ºF. Trim both ends off of a Vidalia onion and then set the onion on one of its cut ends on a piece of foil.
  2. Drizzle the onion with the olive oil and sprinkle with the salt and pepper. Snuggle in the sprigs of thyme (or sprinkle with the dried thyme) .
  3. Wrap the onion tightly in foil and place it in a baking pan.
  4. Roast for about 90 minutes, until a knife inserted into the center of the onion smooshes in very easily.
  5. Remove foil from the onions, but be careful – sometimes there is a bit of onion broth that has come out of the onions (this is especially true of the larger Vidalia onions, not usual with smaller ones). Don’t spill it or discard it. It can be used to flavor dips, soups, sauces, etc.
  6. Let the onions sit until they’re cool enough to touch.
  7. Remove and discard the skins from the onions. (Sometimes there’s an additional outer layer of onion that got a bit dry as well. If this has happened, discard this dry outer layer too. A bit of browning around the edges is fine. It’s a tough, dry, difficult to mash layer that we want to avoid).
  8. Discard the thyme and you’re ready to use your roasted onions in all sorts of delicious ways.
How To Roast Onions So They\'re Sweet, Soft & Creamy

20 responses to “How To Roast Onions So They’re Sweet, Soft & Creamy”

  1. Emma Reynolds says:

    Why don’t you Americans give the oven setting a Celsius equivalent so the rest of the world can follow your recipes – you ALL only give oven settings in Fahrenheit. Surely ‘Preheat the oven to 425ºF/220ºC’ isn’t all that difficult??? :-(

    • Christine Pittman says:

      I’m sorry that this upsets you so much, Emma. I’m Canadian and have spent a lot of time in the UK. I therefore understand how annoying it can be to use equipment that doesn’t align with the recipes you have. I remember my frustration the first time I had to cook with an oven that only had gas marks for temperatures!
      Having said that, the vast majority of my readers are American and a large proportion of them are new to cooking. I have made the choice to use instructions that make sense for them and for their equipment so that they will have as little confusion as possible. I fear that multiple temperatures would be confusing, especially if they’re new and don’t realize that different countries do it differently. If you run into this issue a lot, you might want to print out a conversion chart like this one and keep it somewhere handy https://www.thecalculatorsite.com/cooking/oven-temperatures.php From my experience, once I’d made a few recipes in England using my American recipes, I knew the important conversions by heart and it was no longer a problem. I hope this helps!

  2. Kim Conover says:

    I drizzle balsamic vinegar on the onions when I roast them – just a teaspoon if the onions are very sweet. It really brings out the flavor. I usually quarter the onions and roast heads of garlic with the tops sliced off – all in the same foil. When it cools off, I blend it with a little cream cheese for a thicker spread or split the difference and do half cream cheese, half sour cream for more of a dip. This stretches the onions and garlic for a crowd and doesn’t taste less yummy.

  3. Charlotte says:

    Do you think you could make a French onion soup using this method?

  4. Sabrina says:

    These are great also cut in half and roasted for about an hour in the oven and served with authentic Carnitas.

  5. Paula says:

    V Onion…. nothing better.  Can hardly waiting till they hit Floor markets.   Yummy!!!!

  6. Sakhi says:

    These look delicious! Do they keep well in the fridge?

  7. Chin Beley says:

    Looks delicious going to try this tonight! Thanks!

  8. Katie says:

    This is brilliant! I must give this a try soon since I have a few vidalia’s sitting in my pantry!

  9. Suzanne says:

    This looks like it would be such a great side dish to a comforting meal!

  10. Kim Beaulieu says:

    I am totally trying this one on the weekend. It’s so wicked cool.

  11. So we need to figure out how to become neighbours. You could make that luscious dip and I’ll keep opening bottles of wine.

  12. […] Roasted Vidalia Onions by Cook the Story […]

  13. this might be the best thing I`ve seen all day. Yum!!

  14. Always done this with garlic, never onions. What a great idea!

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