Cooking Tips

Grilling Onions? Keep the Skin On.

 Skin-on cooking is the secret to perfectly caramelized and intact grilled onions.

Published Aug. 15, 2022.

If you’ve ever watched a burnt onion hunk slip through your grill grates, then our recipe for perfectly caramelized Grilled Onions with Balsamic Vinaigrette is for you.

It doesn't require a grill basket or a presoaked wooden skewer to prevent burning or falling. Instead, it calls for one unexpected tip that helps prevent both.

Simply don't peel your onion.

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I know this sounds strange but stick with me. This helps in two ways. 

For starters, grippy onion skin is a benefit because it holds the onions together in their bowl-like shape. It adheres nicely to the interior onion, giving your tongs something to hold onto when flipping gracefully on the grill.

Second, cooking onions directly on the grill ensures that they’ll have sufficient chargrilled flavor—but you run the risk of burning them. After browning the onions over direct heat, we transfer them to a disposable pan to finish cooking. The onion skin actually shields the bottom of the onion from turning black during this caramelization process.

This technique can be applied for any instance where you want perfectly grilled onions. See it in action in this video, where test cook Annie Petito cooks through her grilled onion recipe.

There are a few things to keep in mind when grilling your skin-on onions:

  • When preparing the onions, cut them from pole to pole rather than through the equator. This keeps the root structure (the way the onion naturally grows) intact. 
  • Charring onion halves cooks the outside but not the inside. Transfer them to a covered disposable pan to steam and finish cooking. 
  • Once they finish in that pan, remove the skins. Although technically edible, the blackened skin is sure to taste unpleasant.
  • Before serving, brush the cut sides of the onion with a balsamic vinaigrette. This infuses them with complementary sweet and acidic flavors.


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