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Home » Roasted Onions

Roasted Onions

Diane SmithBy Diane Smith Updated on September 6, 2022
Disclosure: This post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.
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Onions are so wonderful when they’ve been roasted to sweet perfection. This roasted onion dish is a simple, yet super flavorful recipe.  I love using red onions, which tend to be sweeter.

Roasted Onions

How to Roast Onions

After cutting the onions into wedges, toss them into a bowl. Whisk a dressing of red wine vinegar, lemon juice, mustard, garlic, thyme, salt, and pepper, and pour over the onions, stirring to make sure all of them are covered. Roast them to perfection in the oven.

Roasted onions are good for you since they have beneficial effects on the cardiovascular and immune systems, as well as anti-diabetic and anti-cancer effects. See this link for a list of the 6 very best foods, from Dr. Fuhrman.

Not many think of having onions on their own as a side dish, but these are wonderful on a veggie burger, added to your salads, or pasta, topped on your rice or mashed potatoes or mushrooms, or blended into your favorite soup.

Roasted Onions

Onions are a really wonderful vegetable to add to your diet, as they contain high vitamin C that helps to ward off any cases of flu or colds ins the winter season. Onions have also been known to reduce inflammation and are useful in clearing infections. They also contain fiber and folic acid, a B vitamin that regenerates healthy new cells.

There are many varieties of onions to choose from. If you are feeling extra fancy, you can use different kinds in this dish for a melding of flavors.

roasted onions on white serving dish

Onions are also one of those veggies people dislike working with because the smell lingers on your fingers, and they make your eyes water and sting. There are a few tricks chefs use to limit the eye-burning sensation.

Some say to use a wet rag or paper towel near them. Some people also say soaking your onions in water for a few minutes may reduce this enzyme’s intensity.

Enjoy these roasted veggies with your next meal:

  • Kabocha Squash
  • Brussels Sprouts
  • Baby Turnips with Mustard Vinaigrette
  • Curried Cauliflower with Peas
  • Potato Salad

Ultimately, there is something very comforting about the aroma of onions and garlic roasting in the wintertime, adding warmth to any home. Jazz up your recipe with this simple addition.

I’d love to hear your feedback in the comments below for this Roasted Onions! If you have a photo, post it on my Facebook page, tag me using the hashtag #plantbasedcooking in your caption, and I won’t miss it!

 

Roasted Onions
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3.91 from 44 votes
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Roasted Onions

These Marinated Slow Roasted Onions get soft and creamy on the inside and caramelize on the outside roasting in a marinade of red wine vinegar, lemon, and spices.
Prep Time20 minutes mins
Cook Time30 minutes mins
Total Time50 minutes mins
Servings: 4 people

Equipment

  • Cutting board
  • Knife
  • Glass Mixing Bowls with Lids
  • Silicone Cooking Utensil Set
  • Baking Sheet

Ingredients

  • 2 red onions
  • 1 yellow onion
  • 2 tbsp red wine vinegar
  • 2 tbsp freshly squeezed lemon juice
  • 1 tsp dijon mustard
  • 1 tsp minced garlic
  • 1/2 tbsp minced fresh thyme leaves
  • 1/2 tsp salt
  • 1/4 tsp freshly ground black pepper
  • 1/2 tbsp minced fresh parsley leaves
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Instructions

  • Preheat the oven to 400 degrees F.
  • Remove the stem end of each onion and carefully slice off the brown part of the root end, leaving the root intact. Peel the onion. Cut the onion in wedges through the root. Place the wedges in a bowl.
  • For the dressing, combine the red wine vinegar, lemon juice, mustard, garlic, thyme, salt, and pepper in a large bowl. Pour the dressing over the onions and toss well.
  • With a slotted spoon, transfer the onions to a shallow baking pan or sheet, reserving the vinaigrette that remains in the bowl. Bake the onions for 30 to 45 minutes, until tender and browned. Toss the onions once during cooking.
  • Remove from the oven, and drizzle with the reserved dressing. Sprinkle with parsley, season to taste and serve warm or at room temperature.

Notes

Nutrition

Nutrition Facts
Roasted Onions
Amount per Serving
Calories
42
% Daily Value*
Fat
 
0.2
g
0
%
Saturated Fat
 
0
g
0
%
Cholesterol
 
0
mg
0
%
Sodium
 
454.1
mg
20
%
Carbohydrates
 
9.7
g
3
%
Fiber
 
1.8
g
8
%
Sugar
 
4.2
g
5
%
Protein
 
1.2
g
2
%
Vitamin A
 
0
IU
0
%
Vitamin C
 
14.9
mg
18
%
Calcium
 
30
mg
3
%
Iron
 
0.4
mg
2
%
* Percent Daily Values are based on a 2000 calorie diet.
The nutrition information is a rough estimate. Values will vary based on variables like specific brand or type of product used. To obtain the most accurate representation, it’s recommended that you calculate your own with the actual amount and type of ingredient used.
Tried this recipe?Tag @PlantBasedCooking on Intagram!

Leave a Comment and Star Rating ⭐️⭐️⭐️⭐️⭐️

I appreciate your feedback! Please consider rating the recipe along with your comment—it helps me and fellow readers. Feel free to share any substitutions, results, or tips. Kind, constructive comments only. Your email won’t be published.

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About Diane Smith

Diane Smith is a certified plant-based nutrition educator, Food Over Medicine instructor, recipe developer, and founder of PlantBasedCooking.com. She helps people transition to a whole-food, plant-based lifestyle with simple recipes, practical nutrition guidance, and realistic strategies for improving health, preventing disease, and aging well.

Reader Interactions

Comments

    3.91 from 44 votes (43 ratings without comment)

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    Recipe Rating




  1. Deb

    September 6, 2022 at 4:59 am

    4 stars
    Did I miss the red wine vinegar? The lemon worked as well, but will try it with the vinegar next time.

    Reply
    • Diane Smith

      September 6, 2022 at 12:56 pm

      Hey Deb, I just updated the recipe to include it now. Thanks for bringing that to my attention. I’m glad you enjoyed the recipe.

      Reply

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roasted onions on white serving dish
roasted onions on white serving dish

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