Roasted Onions with Thyme

These Roasted Onions with Thyme are an ideal side dish, easy enough for weeknight meals as well as being a perfect addition to your festive table.  The simple process of roasting the onions totally transforms them; as they cook, their sugars caramelise, enhancing their natural sweetness. And they are so easy to make! Just add the trimmed, halved onions to a baking dish along with some olive oil, season with salt, pepper and sprigs of thyme then roast. A drizzle of sweet, yet tart, Balsamic Glaze just before serving takes this side dish to new heights.

You will love these Roasted Onions with Thyme because:

• This is a healthy side dish that is easy to make and full of flavour, as well as being budget-friendly.
• You can transform an everyday ingredient into a full-flavoured side dish which will be ideal to serve with meat, fish or poultry such as our Spatchcock Chicken. As well, they are a great addition to salads, added to a sandwich or wrap or served at a barbecue.
• The Roasted Onions are naturally gluten-free and vegan, making them suitable for many people with specific dietary requirements.
• Whether you are cooking for a large or small number of people, you can scale this recipe up or down, depending on your requirements.

Ingredients in this recipe:

Please see the recipe card further along in the post for exact quantities of ingredients and the full method.

Brown/yellow and red onions – we use two varieties for the colour variation, but you can use any onion that you prefer. The red onion is sweeter than the brown/yellow or white onion.

Extra virgin olive oil – this is our preference for flavour and nutritional benefit. Use the best olive oil that you have.

Fresh thyme – a few sprigs of this aromatic, fresh herb add great flavour to the onions.

Sea salt and freshly ground black pepper – add to suit your taste.

Balsamic glaze – optional, but is fantastic when serving. It adds a sweet, tart flavour that perfectly complements the Roasted Onions.

How to Roast Onions:

Please see the recipe card further along in the post for exact quantities of ingredients and the full method.

1 – Place your onions in a baking dish:
Preheat your oven to 200 degrees C (390 F).

Cut the onions in half lengthways, and peel. Trim the stem end and leave the root intact to hold the onion halves together.

In a small cast iron skillet or baking dish, place the onions cut side up and drizzle with the olive oil. Top with the sprigs of thyme and season with salt and pepper.

2 – Roast until tender:
Roast for 35 minutes, turning the onions over halfway through to ensure even cooking.

Remove from the oven when they are tender. Arrange on a serving platter and drizzle with balsamic glaze.

Tips for success and FAQs:

When a recipe has so few ingredients, it is essential that they be of the best quality. Choose onions that are heavy in your hand, firm, with dry, papery skins and free of blemishes. Avoid any with soft spots, signs of sprouting or a strong odour. For the best appearance and even cooking, choose onions of a similar size.

What variety of onion is best to use?

You can use most onions for roasting. Here’s a little information on some suitable varieties to use:

Brown/yellow onions – this is the most versatile onion and the variety most used as an all-rounder. This variety includes globe onions and the slightly sweeter Spanish onions.

White onions – this variety is named for its white flesh and thin white skin. Their flavour is milder than brown or red onions.

Red onions – also known as purple onions, they are sweeter than brown/yellow and white onions.

Sweet onions – these onions have a mild flavour. They have a lower sulphur content which makes their sugar content more noticeable. Popular varieties are Vidalias, Walla Wallas and Mauis.

Cipollini – this is an Italian heirloom onion variety. Their name, in Italian, means “little onion”. Cipollini is a more uncommon variety of onion, but they are worth seeking out. The onions are a flat, saucer shape with thin, papery skins. These onions contain more natural sugar than regular white or brown onions, and as such, when roasted they caramelise beautifully.

Serving suggestions:

These Roasted Onions are a great addition to a barbecued steak, hamburger, or any roast meal, along with my Whole Roasted Baby Potatoes or Roasted Tenderstem Broccoli.

As well, for a light meal or vegetarian appetiser, serve the Roasted Onions on a bed of rocket, drizzled with Balsamic Glaze and scattered with some fresh goat cheese or feta. The mild acidity of the cheese beautifully complements the sweetness of the onions. 

They also make a delicious appetiser. Make some Crostini, spread them with soft goat cheese and top with some onion and a sprinkle of fresh thyme leaves.

This easily made dish of Roasted Onions is a must for all onion lovers. With just a few simple ingredients, the humble onion is transformed into a side dish which is a guaranteed crowd-pleaser. I look forward to hearing if you try it.

Alex xx

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