Crispy fried onions are a delicious topping that instantly adds crunch, flavor, and texture to casseroles, burgers, salads, sandwiches, and soups. Making them in the air fryer is a lighter and faster alternative to deep frying while still delivering beautifully golden and crunchy onions. These homemade crispy onions have a rich savory flavor with a perfectly crisp coating that tastes fresher and more flavorful than store-bought versions.
Using the air fryer allows the onions to become evenly crisp with only a small amount of oil. The circulating hot air removes excess moisture from the onions while creating a crunchy outer layer without the mess of hot oil or complicated frying methods. This easy recipe is ideal for holiday casseroles, quick garnishes, or everyday cooking when you want restaurant-style crispy onions at home.
The key to perfectly crispy onions is slicing them thinly and coating them lightly so they crisp rather than steam. A quick soak in buttermilk helps soften the onions slightly while allowing the seasoned flour coating to stick better during cooking. The result is golden, crunchy onion strands that stay crisp and flavorful for hours after cooking.
These air fryer crispy fried onions can be prepared ahead of time and stored in an airtight container for later use. Sprinkle them over green bean casserole, mashed potatoes, burgers, mac and cheese, or creamy soups for an irresistible crunchy finish that elevates almost any savory dish.
Preparation Time
- Prep Time: 15 minutes
- Cook Time: 12–15 minutes
- Total Time: 30 minutes
- Servings: 4
Ingredients
For the Fried Onions
- 2 large yellow onions, thinly sliced
- 1 cup buttermilk
- ¾ cup all-purpose flour
- 2 tablespoons cornstarch
- 1 teaspoon garlic powder
- 1 teaspoon paprika
- ½ teaspoon salt
- ½ teaspoon black pepper
- Cooking spray or olive oil spray
Instructions
Step 1: Slice the Onions
Peel the onions and slice them into thin rings or strips using a sharp knife or mandoline slicer for even thickness.
Step 2: Soak the Onions
Place the sliced onions into a bowl and pour the buttermilk over them. Let them soak for 10 minutes to soften slightly and help the coating stick.
Step 3: Prepare the Coating
In a separate bowl, whisk together flour, cornstarch, garlic powder, paprika, salt, and black pepper.
Step 4: Coat the Onions
Remove the onions from the buttermilk and allow excess liquid to drip off. Toss the onions in the flour mixture until evenly coated.
Step 5: Preheat the Air Fryer
Preheat the air fryer to 350°F (177°C) for 3 minutes.
Step 6: Air Fry the Onions
Lightly spray the air fryer basket with cooking spray. Arrange the coated onions in a thin layer in the basket without overcrowding.
Spray the tops lightly with cooking spray and air fry for 10–15 minutes, shaking the basket every 4–5 minutes, until the onions are golden brown and crispy.
Cook in batches if necessary for best crispiness.
Step 7: Cool and Serve
Transfer the crispy onions to a plate lined with paper towels and allow them to cool slightly. They will become even crispier as they cool.
Air Fryer Settings
| Air Fryer Type | Temperature | Time |
|---|---|---|
| Basket Air Fryer | 350°F (177°C) | 10–15 mins |
| Oven-Style Air Fryer | 345°F (174°C) | 12–16 mins |
| Thin Onion Strips | 340°F (171°C) | 8–12 mins |
Nutritional Facts (Per Serving)
| Nutrient | Amount |
|---|---|
| Calories | 180 |
| Protein | 4g |
| Carbohydrates | 29g |
| Fat | 5g |
| Saturated Fat | 1g |
| Cholesterol | 4mg |
| Sodium | 320mg |
| Fiber | 2g |
| Sugar | 5g |
Nutrition values are approximate and may vary depending on ingredients used.
Tips for Best Results
- Slice onions evenly for consistent cooking and crispiness.
- Do not overcrowd the air fryer basket or the onions may steam instead of crisp.
- Spray lightly with oil to help achieve a golden crunchy texture.
- Shake the basket several times during cooking for even browning.
- Use sweet onions for a milder flavor or red onions for extra color.
- Store cooled crispy onions in an airtight container for up to 3 days.
- Re-crisp leftover onions in the air fryer at 325°F for 2–3 minutes before serving.

