Roasted Red Onions with Basil, Fennel Seeds, and Balsamic Glaze
These members of the Allium genus are covered with a red parchment-like skin, and their deep purple and white variegated interior is a glory to behold.
Even raw these onions are on the sweet side, but a long roast in a fast oven transforms them into meltingly soft mouthfuls, dark and sweet as candy. If you are looking for an addition to a platter of mixed vegetables, a topping for a toasty bruschetta or an accompaniment to roasted meats, try these red onions. Their sweetness is heightened by aromatic basil, its hint of licorice a perfect match for the taste and crunch of fennel seeds, blasts of chunky sea salt and the velvety richness of a fine balsamic glaze.
Let your taste be your guide with the basil, lush balsamic syrup, and a glistening sprinkle of coarse sea salt, adding more or less, as you please. Large red onions must be cut into eight pieces each, their woody stem ends cut away; these tough ends will not soften sufficiently during roasting and may pose a choking hazard to diners. Carefully cut away the tough end pieces, taking care to leave enough to hold the onions together. Smaller onions may be cut into quarters or sixths. As good as these onions are tossed with the basil, they get even better with a few dabs of Taleggio or Gorgonzola dolce. The cheeses melt into the onions adding another layer of flavor.
A number of rich balsamic glazes are available now. Trader Joe’s sells a nice one, but look to Acetaia Reale for a uniquely sumptuous indulgence and true balsamic flavor. Acetaia Reale is available from Olio2Go.
Be sure to check fennel seeds for freshness. Spices do not last forever, and if you don’t get a hefty scent of fennel when you open the jar of seeds, it is time to buy new. Fennel is native to the Mediterranean, and is also known as Sweet Cumin. The seeds are available at supermarkets and at many specialty spice purveyors, such as Penzeys Spices and Savory Spice Shop, both online and at each company’s brick and mortar stores.
Roasted Red Onions with Basil, Fennel Seeds, and Balsamic Glaze
The onions may be served right from the oven, warm or at room temperature. Topped with cheese, they are best served warm.
2 pounds red onions
½ cup extra virgin olive oil
1 ½ teaspoons fennel seeds
1 tablespoon coarse crystal sea salt
½ cup whole basil leaves, whole or cut in chiffonade
Acetaia Reale Balsamic Glaze, as desired
Optional Gorgonzola dolce or Taleggio
Preheat the oven to 400 degrees F. Cut the red onions into eighths if large, sixths, or quarters if small. Toss very gently to coat with olive oil. Place the onions in a 9X9 ovenproof dish, and sprinkle with the fennel seeds. Place the baking dish on the middle rack of the oven and roast for 1 hour to 1 hour and 10 minutes, until the onions have softened and caramelized.
Remove the onions from the oven, and spoon some of the oil from the baking dish over them to coat. Drizzle with Acetaia Reale Balsamic Glaze, and sprinkle with coarse sea salt. Tuck whole basil leaves among the onions or top with cut basil and serve.
If the onions are to be served with the optional cheese, dab chunks of either Gorgonzola dolce or Taleggio atop the onions while still quite warm and serve immediately.
Adapted from Nigellissima by Nigella Lawson
Acetaia Reale Balsamic Glaze is available from Olio2Go.
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I have no affiliation with any product, manufacturer, or site mentioned in this article.
Photo of Acetaia Reale Balsamic Glaze courtesy Olio2Go
Friday, May 16th 2014 at 6:07 am |
Adri, I love this simple but elegant side dish. I love how sweet onions get when you roast them and the balsamic glaze is so good. It is so easy to make your own glaze if you can\’t get it from the store as sometimes these specialty items are difficult to find in Asia.
On a side note, do you order your olive oils from a particular vendor? I so need another trip to Italy or at least a good vendor who can tie me over until next visit. Take Care, BAM
Friday, May 16th 2014 at 7:59 am |
Hi Bam!
These onions are remarkably sweet. The oven roasting just makes them delectable. I hope you try them. I get my oils form Olio2Go.com, a store with an immense selection of truly fine oils. Take a look at their site. Every oil is first rate, and the descriptions are most informative. There is not a bad one among them, and you are assured of fresh oil. Thanks for stopping by.
Saturday, May 17th 2014 at 2:51 am |
Nothing to do with your great recepits . My request is: can you give us some way to enjoy fava beans?
Thanks a million
Thursday, May 22nd 2014 at 4:36 pm |
I don’t think I can make this one fast enough! What perfect simplicity this dish is… I love roasted onions (especially the red ones) and the addition of fennel takes this over the top. I love using fennel seeds. When I worked at a restaurant, we used to stuff small roasted red onions with creamed kale, and served it as a side dish. It was heavenly. Lovely recipe Adri!
Friday, May 23rd 2014 at 7:42 am |
Hi Emilie,
These are as sweet as candy, and you will love them. We could not stop eating them. The stuffed onions you describe sound wonderful. I think fennel seeds do not get enough respect!
Friday, May 23rd 2014 at 9:09 am |
Oh wow, these look SO lovely! I’d love these topped with a little cheese, as you mention, and they served with some freshly-baked bread. Mmmmmm.
Friday, May 23rd 2014 at 9:49 am |
Hi Amy,
These really are great. At first I thought they were “Winter food” – best with roasted meat. But then after we began to eat them I realized they would be terrific atop bruschetta – so I think we’ll be enjoying these as a summer antipasto. I hope you try them. They are as sweet as candy!
Thursday, July 24th 2014 at 7:33 am |
we love roasted veggies! summer time yields for so much variety!
Thursday, July 24th 2014 at 7:53 am |
Hello to you both,
Roasted veggies are perfect summer food. They pair so nicely with grilled met. Enjoy, and thank you for stopping by!
Thursday, September 4th 2014 at 4:55 pm |
Onions cooked down with balsamic or wine are a godsend. They perk up so many dishes — from a burger to an omelet.
Thursday, September 4th 2014 at 7:45 pm |
Hi Carolyn,
You are so right. I never enjoy raw onions but cook them down and caramelize them, and I’m in heaven. They are like candy. Thanks for stopping by.
Thursday, September 11th 2014 at 6:53 am |
Oh god! It looks sooooo good! I love it!
Thursday, September 11th 2014 at 9:09 am |
Hi Marcela,
Thanks! I just love the flavor combinations with this one. Un bacione a te!