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Air fryer baked whole onions with caramelized golden layers, tender sweet centers, fresh parsley, and a drizzle of olive oil, served as a simple and flavorful vegetable side dish.
Print Recipe

Air Fryer Baked Whole Onions - Sweet, Tender, and Effortless

Prep Time10 minutes
Cook Time35 minutes
Total Time45 minutes
Servings: 4 servings

Ingredients

  • 4 medium onions (yellow, white, or sweet like Vidalia)
  • 2 tablespoons unsalted butter, softened (or 2 tablespoons olive oil for dairy-free)
  • 1 teaspoon kosher salt
  • 1/2 teaspoon freshly ground black pepper
  • 1 teaspoon garlic powder (or 2 minced garlic cloves)
  • 1 teaspoon dried thyme or rosemary (optional)
  • 1 tablespoon balsamic vinegar or lemon juice (optional, for finishing)
  • Fresh parsley or chives, chopped (optional, for garnish)

Instructions

  • Preheat the air fryer: Set it to 375°F (190°C). Preheating helps the onions brown more evenly.
  • Prep the onions: Peel the papery outer layers and trim just the root fuzz without cutting through the base. Slice about 1/4 inch off the top so you have a flat surface.
  • Score for flavor: Make a deep “X” cut on the top of each onion, going about two-thirds of the way down. This helps the butter and seasoning sink in.
  • Season: Rub each onion with butter or drizzle with olive oil. Sprinkle with salt, pepper, garlic powder, and herbs if using. Press a little butter into the top cuts for extra richness.
  • Air fry: Place onions upright in the basket, leaving space between them. Cook for 30–40 minutes, depending on size. They’re done when a knife slides in easily and the tops are browned.
  • Finish: Drizzle with balsamic vinegar or a squeeze of lemon while hot. Let them rest for 5 minutes so the juices settle.
  • Serve: Spoon the soft layers apart and garnish with fresh herbs. Serve as a side, or slice and pile over steak, burgers, grains, or roasted veggies.