Pin It A sweet tender Vidalia onion roasted whole until meltingly soft with aromatic herbs and butter is a simple yet elegant side dish.
I remember discovering the magic of roasted sweet onions on a spring picnic. The flavor was so rich it instantly became the star of our meal.
Ingredients
- Vidalia onions: 4 large unpeeled (or other sweet onions)
- Unsalted butter: 4 tbsp
- Fresh thyme: 4 sprigs
- Garlic: 4 cloves peeled
- Kosher salt: 1 tsp
- Freshly ground black pepper: ½ tsp
- Fresh parsley: 2 tbsp chopped (optional garnish)
Instructions
- Preheat Oven:
- Preheat your oven to 400°F (200°C).
- Prep Onions:
- Trim just the root ends and tops so onions sit flat. Leave skins on. Cut a shallow X in the tops with a paring knife.
- Season:
- Place each onion on heavy-duty foil. Sprinkle with salt and pepper. Press 1 tbsp butter 1 sprig thyme and 1 garlic clove into the cut top of each onion.
- Wrap and Roast:
- Wrap each onion tightly in foil. Arrange on a baking sheet. Roast for 1 hour 10 minutes until onions are very tender when pierced.
- Unwrap and Serve:
- Carefully unwrap remove skins and transfer to serving plates. Spoon over melted butter from foil. Sprinkle parsley if desired.
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My daughter loves helping wrap the onions in foil and always sneaks extra parsley on top for a pop of color.
Serving Suggestions
This dish pairs beautifully with roast meats grilled vegetables or crusty bread for a vegetarian main.
Required Tools
Baking sheet heavy-duty foil paring knife and an oven are all you need for this fuss-free dish.
Allergen & Nutritional Info
Contains dairy. For dairy-free use vegan butter or olive oil. Each serving has 130 calories 7g fat 19g carbohydrates and 2g protein.
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Try this simple oven method and enjoy onions like never before. It makes any meal memorable.
Recipe Questions & Answers
- → What type of onion works best?
Sweet onions like Vidalia, Walla Walla, or Maui provide a tender, mild flavor ideal for roasting.
- → How should onions be prepared before roasting?
Trim root ends and tops to sit flat, cut a shallow X on top, and season with butter, garlic, thyme, salt, and pepper before wrapping in foil.
- → Why is foil used during cooking?
Wrapping in foil traps steam and helps onions soften evenly while preserving moisture and infused flavors.
- → Can the cooking time be adjusted?
Roasting for about 1 hour 10 minutes ensures maximum tenderness; shorter times may leave onions firmer.
- → What garnishes complement this dish?
Fresh parsley adds color and brightness, while optional additions like balsamic vinegar or smoked paprika enhance depth.
- → Is this suitable for special diets?
Yes, it is naturally vegetarian and gluten-free; dairy-free versions can use vegan butter or olive oil.