This easy Grilled Balsamic Onions recipe transforms ordinary sweet onions into a sweet, tangy, and richly caramelized side. With just a handful of pantry ingredients—sweet onions, balsamic vinegar, olive oil, salt and pepper—these onions marinate and slow-grill until their natural sugars bloom and the balsamic adds depth and complexity to every bite. They make an ideal accompaniment for steaks, chops, sandwiches, and grilled vegetables.
Grilled Balsamic Onions
These grilled balsamic onions are a simple way to bring a steakhouse touch to your backyard cookout. They pair especially well with rich beef like American Wagyu hanger steak, grilled pork chops, or as a savory topping for burgers and sandwiches. The brief marination lets the onions soak up balsamic’s acidity and sweetness, and slow grilling gently carmelizes them without losing texture.
The method is straightforward: slice the onions, season, coat with balsamic and olive oil, let them rest in the refrigerator to marinate, then cook slowly on a grill or smoker. The result is tender, slightly translucent onions with a glossy balsamic finish and a balanced sweet-tangy flavor.
Why You’ll Love This Dish…
- Deep flavor: Caramelization and balsamic create rich, layered taste.
- Minimal ingredients: Uses common pantry staples you likely already have.
- Versatile: Works as a side, topping, or addition to salads and sandwiches.
- Low hands-on time: Most of the time is hands-off while the onions cook.
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Recipe Shopping List
Everything you need is simple and easy to find. Quantities are shown in the recipe card below.
- Sweet onions (large)
- Salt
- Black pepper
- Balsamic vinegar
- Olive oil
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How To Make This Recipe
Below is a clear, step-by-step overview so you know what to expect while cooking. A printable recipe card with exact quantities and times appears further down.
- Prepare: Trim the onions and slice into 1/3-inch rounds.
- Season: Salt and pepper both sides of each slice.
- Arrange: Coat a rimmed cookie sheet with olive oil and lay the onions in a single layer.
- Marinate: Pour balsamic over the onion slices, refrigerate for 1 hour, flipping halfway through so both sides soak up flavor.
- Preheat: Heat your grill or pellet smoker to 300°F (150°C).
- Grill: Place the cookie sheet on the grill; cook about one hour, checking every 20 minutes to prevent the balsamic sugars from burning.
- Finish: The onions are done when mostly translucent with a small white center; remove and serve immediately.
Try these Smoked Cipollini Onions!
Recipe FAQ
How do I store leftover Grilled Balsamic Onions?
Keep leftovers in an airtight container in the refrigerator for up to four days. Reheat gently to preserve texture.
Can I reheat Grilled Balsamic Onions?
Yes. Reheat in a skillet over medium heat until warmed through, or use a microwave for a quick option. Stir occasionally to prevent sticking and burning.
Can I prepare this dish in advance?
Absolutely. You can marinate the onions overnight in the refrigerator and grill them the next day. If marinated longer, watch closely while grilling since the sugars may brown faster.
Try these next to our Grilled Tomahawk Steak!
Serve This With…
- Grilled Pork Chops
- Grilled Flat Iron Steak
- Flank Steak
- Grilled Dinner Rolls
- Caesar Salad
Side Dish Recipes
- Traeger Jalapeño Cheddar Cornbread Muffins
- Jalapeño Cheddar Corn Cakes
- Instant Pot Basmati Rice
More Recipes Featuring Onions
- Smoked Onion Jam
- Smoked French Onion Soup
- Smoked Caramelized Onion Dip
- Smoked Caramelized Onion Butter
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Yield: 4 servings
Grilled Balsamic Onions
A simple, flavorful side that complements steak, pork, and grilled breads. Easy to prepare and full of caramelized, tangy-sweet flavor.
Prep Time: 5 minutes
Cook Time: 1 hour
Total Time: 1 hour 5 minutes
Ingredients
- 2 large sweet onions
- ½ teaspoon kosher salt
- ½ teaspoon black pepper
- ½ cup balsamic vinegar
- 3 tablespoons olive oil
Instructions
- Trim and slice the onions into 1/3-inch thick rounds.
- Season both sides of each slice with salt and pepper.
- Coat the bottom of a rimmed cookie sheet with the olive oil and arrange the onion slices in a single layer.
- Pour the balsamic vinegar evenly over the onions.
- Refrigerate the sheet for 30 minutes, flip the onions, then refrigerate another 30 minutes to marinate.
- Preheat your grill or pellet smoker to 300°F (150°C).
- Place the cookie sheet on the grill and cook for about one hour, checking every 20 minutes to prevent burning.
- If the balsamic begins to darken too quickly, lower the grill temperature.
- Remove when the onions are mostly translucent with a small bit of white center remaining. Serve immediately.
Nutrition Information (per serving)
Calories: 174 · Total Fat: 11g · Saturated Fat: 1g · Unsaturated Fat: 9g · Sodium: 312mg · Carbohydrates: 18g · Fiber: 2g · Sugar: 13g · Protein: 2g