Make perfect grilled onions every single time with my amazing grilled onion hack! The perfect addition to so many meals, this post will teach you how to sauté onions with a quick and easy method. Plus, a secret ingredient!

What Makes This Recipe Great

Onions Grilled to Perfection, Every Single Time!

It still blows my mind that onions, such a strong-tasting vegetable, can cook down into something so sweet and caramelized. The flavor is completely transformed and you end up with tender, delicious onions! Sautéed onions are so versatile, and delicious, and go with just about everything!

I love onions grilled for burgers, pizzas, sandwiches, breakfast, and even on my salads, but they have to be cooked just right. The first few times I made them it was a complete disaster. As in, the smoke detector went off and I was left with a pan full of charred remnants of what used to be an onion.

So to help you avoid the same mistakes, here is exactly how I make sautéed onions, grilled perfectly in my cast iron pan, every single time!

ingredients to make grilled onions

Ingredient Notes

All you need are four ingredients to make these caramelized onions:

Onions: You can use Vidalia onions (sweet), yellow onions, or red onions. Take your pick!

The rest of the ingredients are salt, butter… and my absolutely amazing hack: water. I know it sounds weird, but trust me, it’s the best hack!

Recipe Step by Step

step by step instructions on how to make the perfect caramelized onions
  1. Slice the onions like in the photo above (about 3/8″ thick). You can cut the onion in different ways, but I prefer them like this.
  2. Warm up your skillet over medium heat.
  3. Add the onions butter, and kosher salt, and cook, stirring frequently.
  4. Serve the sauteed onions with a variety of side dishes, entrees, and meals!

My Amazing Grilled Onion Hack

WATER! As soon as the onions start to look a little dry, add a few tablespoons of water. This will prevent the onions from drying out and will keep them juicy and cooking at an even temperature.

The water will evaporate as you are cooking the onions, leaving you with perfectly juicy onions grilled to absolute perfection. As you saute the onions, their natural sugars release into a beautiful caramelized flavor.

pouring water into the pan while sauteeing onions

Which Onions Are Best for Grilling?

This recipe will work with yellow onions, white onions, red onions, sweet onions, etc! Basically, whatever flavor profile you’re looking for, choose that onion and grill it!

Red Onion: great for steak, burgers, sandwiches, and salads!

Yellow Onion: milder in flavor, great with burgers, stir fry, fajitas, casseroles, and other Mexican-inspired dishes.

Sweet Onion/Vidalia Onion: a mild flavor with a hint of sweetness, great with pizza, pasta, and sauces.

Ways to Serve Grilled Onions

Some people eat sautéed onions by themselves with salt and pepper, and a dash of balsamic vinegar.

Grilled onions are also great for:

burgers

salads

sandwiches

casseroles

fajitas

stir-fry

sauces

pizza

steak dishes

pasta

tacos

Expert Tips

Dairy Free/Vegan: If you need these sautéed onions to be dairy free, you can use coconut oil or olive oil for grilling onions in place of butter or ghee.

Storing: Leftovers will keep in an airtight container refrigerated for at least 5 days, or frozen for at least 6 months. You can enjoy them cold out of the fridge, or rewarm them in the microwave or skillet.

FAQs

Is grilling onions keto-friendly?

Yes! Onions are super low in carbs and make for a great, flavorful addition to any keto-friendly meal. Sautéed onions grilled with butter makes the fat content higher, helping you reach your daily macros!

Can I freeze grilled onions?

Yes! They can be frozen for at least 6 months. You can enjoy them thawed and cold out of the fridge, or reheated in the microwave or skillet.

Are these grilled onions Whole30 compliant?

Use ghee or coconut oil to keep your onions grilled with Whole30-friendly ingredients.

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Perfect Grilled Onions Hack!

Make perfect grilled onions every single time with my amazing grilled onion hack! The perfect addition to so many meals, this post will teach you how to sauté onions with a quick and easy method.
4.82 from 16 ratings

Ingredients 
 

  • 1 large yellow onion, sliced
  • 2 tablespoons butter or ghee
  • 1 teaspoon kosher salt
  • water

Equipment

Instructions 

  • Heat your cast iron skillet over medium heat.
  • Add the butter, onions and kosher salt. Cook stirring every few minutes.
  • As soon as the onions start to look a little dry, add in a few tablespoons of water. This will both prevent the onions from drying out and keep them juicy and cooking at an even temperature. The water will evaporate as it cooks, leaving you with perfectly juicy onions. I usually add water twice during the cooking process.
  • Continue to grill the onions uncovered until they are soft and golden brown. About 30 minutes.
  • Serve warm or cold.
  • See the Recipe Notes below for more tips, FAQ's and recipe substitutions.

Notes

Onion: You can also use white or red onion.
Dairy Free/Vegan: If you need these to be dairy free, you can use coconut oil to grill onions in place of butter or ghee. 
Whole30: Use ghee or coconut oil to keep these Whole30 friendly.
Storing: Leftovers will keep in an airtight container refrigerated for at least 5 days, or frozen for at least 6 months. You can enjoy cold out of the fridge, or rewarm in the microwave or in the skillet.
Calories: 236, Total Carbs: 7.5g, Protein: 1.1g, Fat: 23.1g, Fiber: 1.4g, Net Carbs: 6g
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