Food

Roasted Onions: 3 Foods to Pair With Roasted Onions

Written by MasterClass

Last updated: Sep 9, 2021 • 4 min read

Roasted onions can accompany main courses, or you can combine them with other roasted vegetables for the ultimate side dish.

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What Are Roasted Onions?

Roasted onions are onions that you cook in the oven at a high temperature until they become soft and golden brown. You can serve them in a variety of ways, including on top of stea.

To make roasted onions, you slice the onions (usually discarding the root ends) and then cook them at around 375 degrees Fahrenheit.

How to Make Roasted Onions

Making roasted onions can be a fairly straightforward process, even for beginner cooks, as long as you start with quality onions and the right equipment. Follow these steps to make roasted onions:

  1. 1. Select the onions. Any onion stands up to roasting, and sweet onions like red onions and Vidalia onions will become even sweeter. Yellow onions and white onions take on sweetness but retain more of a typical onion flavor. For whole roasted onions, look for medium onions—with larger onions, the outside can overcook before the inside cooks at all.
  2. 2. Choose the cut. Slice, quarter, or keep the onions whole. The oven temperature you use will be the same no matter the cut, but the cook time changes. This is important if the roasted onions are part of a side dish and you plan to serve them with a composed meal. Additionally, the smaller the cut of the onion, the more maintenance they require while roasting. For thinly sliced onions, you will have to stir them regularly so they don’t burn.
  3. 3. Don’t crowd the pan. If there are too many onions and they are too close together, the onions will steam rather than roast. Place the onions, no matter how they’re cut, on a baking sheet or in a baking dish with enough space around them for the hot air to circulate. For roasted caramelized onions, this matters less because you will toss them often while roasting. For all other cuts, place them in a single layer with the cut side down.
  4. 4. Apply light seasoning. The roasting process intensifies flavor, so any seasoning you add will also intensify—too much salt yields an oversalted roasted onion and too much pepper might be too spicy. Lightly sprinkle black pepper and Kosher salt or sea salt over the onions. You might also choose to place sprigs of fresh thyme or fresh rosemary around the onions on the baking sheet or baking dish. Toss the onions with olive oil.
  5. 5. Roast at the right temperature. For roasting a veggie like an onion, crank up the heat. The lowest ideal temperature is 375 degrees Fahrenheit, but taking the oven up to 400 degrees Fahrenheit can result in a more deeply roasted onion. Sliced onions take much less time and require a closer eye so that they don’t burn. It is possible to make oven-roasted caramelized onions or even slow cooker caramelized onions, but they are prone to burning if you are not able to watch them closely and toss them regularly.
  6. 6. Adjust the seasoning. It’s possible to underseason the onions prior to roasting them in order to prevent overseasoning. If that happens, you can sprinkle additional salt, pepper, or other seasonings over the onions once you’ve taken them out of the oven. Balsamic vinegar can also be a good seasoning—drizzle balsamic over the hot onions and toss them to coat each onion.

3 Foods to Pair With Roasted Onions

Roasted onions are versatile in flavor and pair well with other vegetables and proteins, whether you choose to make them as a side dish or as part of a vegetarian main course. Green beans, Brussels sprouts, butternut squash, whole shallots, and potatoes all roast well at the same temperature as whole or quartered onions. Here are a few foods that pair nicely with roasted onions:

  1. 1. Crispy loaded french fries: Roasted onions are a popular topping for loaded French fries because they offset the creaminess and saltiness of the French fries. Roast the onions in small pieces, or chop up whole roasted onions. Add sour cream and chives for a loaded baked potato vibe.
  2. 2. Grilled steak: Steak and roasted onions are two savory flavors that pair well because seasonings like thyme and rosemary will complement them both. Top a grilled steak with roasted caramelized onions to balance the flavor of the steak with a touch of sweetness.
  3. 3. Mashed potatoes: Enhance mashed potatoes with chopped roasted onions. Make a normal mashed potatoes recipe or a garlic mashed potatoes recipe and serve the side dish with the roasted onions on top. Alternatively, mix the onions right into the mashed potatoes.

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