Sweet Vidalia Onion Roast

Featured in: Everyday Cozy Plates

This dish features whole Vidalia onions roasted to tender perfection, infused with fresh thyme, garlic, and butter. The onions become meltingly soft, releasing their natural sweetness enhanced by gentle seasoning. Wrapped in foil and slow-roasted, each onion offers a rich, aromatic bite. Perfect as a simple yet elegant side, it pairs beautifully with roasted meats or grilled vegetables, and can be customized with optional parsley garnish for a fresh finish.

Updated on Tue, 18 Nov 2025 16:28:00 GMT
Golden, tender Onion Boil, baked with herbs and butter, ready to serve with crusty bread. Save to Pinterest
Golden, tender Onion Boil, baked with herbs and butter, ready to serve with crusty bread. | velvetthyme.com

A sweet, tender Vidalia onion roasted whole until meltingly soft with aromatic herbs and butter: a simple yet elegant side dish.

The first time I made these onions was for a holiday dinner. They quickly became my family's favorite: perfectly soft and full of rich, herb-infused flavor in every bite.

Ingredients

  • Vidalia onions: 4 large, unpeeled (can substitute Walla Walla or Maui)
  • Unsalted butter: 4 tbsp for rich flavor and moisture
  • Fresh thyme: 4 sprigs to add an aromatic touch
  • Garlic: 4 cloves, peeled for earthy taste
  • Kosher salt: 1 tsp for seasoning
  • Freshly ground black pepper: ½ tsp for subtle heat
  • Chopped fresh parsley: 2 tbsp, optional garnish

Instructions

Prepare Oven:
Preheat your oven to 400°F (200°C).
Trim Onions:
Trim root ends and tops of each onion so they sit flat but leave skins on.
Score:
Use a paring knife to cut a shallow X into the top of each onion.
Season:
Place each onion on heavy-duty foil. Sprinkle each with salt and black pepper.
Add Flavor:
Press 1 tbsp butter, 1 sprig thyme, and 1 garlic clove into the cut top of each onion.
Wrap:
Wrap each onion tightly in foil, set on a baking sheet.
Roast:
Roast 1 hour 10 minutes, until tender when pierced with a knife.
Finish:
Carefully unwrap, remove skins, and place on serving plates. Spoon melted butter from foil. Sprinkle parsley if desired.
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| velvetthyme.com

Sharing these onions at family gatherings has become a tradition. Even picky eaters reach for seconds and love scooping the soft onion layers onto crusty bread.

Serving Suggestions

Pair Onion Boil with roast meats, grilled vegetables, or offer as a vegetarian main alongside warm, crusty bread.

Flavor Variations

Add a splash of balsamic vinegar or pinch of smoked paprika before roasting for extra depth and a gentle tang.

Required Tools

Use a baking sheet, heavy-duty aluminum foil, a paring knife, and your oven for effortless preparation.

Steaming-hot whole Onion Boil, glistening with melted butter and fresh thyme, a savory side. Save to Pinterest
Steaming-hot whole Onion Boil, glistening with melted butter and fresh thyme, a savory side. | velvetthyme.com

Enjoy Onion Boil hot from the oven: a simple recipe that brings warmth and sweetness to any meal.

Recipe FAQs

What type of onions work best for this dish?

Sweet onions like Vidalia, Walla Walla, or Maui are ideal due to their mild, natural sweetness and tender texture after roasting.

Why wrap the onions in foil before roasting?

Wrapping in foil traps moisture, allowing the onions to steam and become soft while infusing flavors from butter and herbs.

Can I add other seasonings to enhance flavor?

Yes, adding balsamic vinegar or smoked paprika before roasting can introduce additional depth and complexity.

How do I know when the onions are fully cooked?

They should be easily pierced with a knife and feel meltingly tender throughout after about 1 hour 10 minutes in the oven.

What dishes pair well with roasted Vidalia onions?

They complement roasted meats, grilled vegetables, or work as a flavorful vegetarian accompaniment with crusty bread.

Sweet Vidalia Onion Roast

Vidalia onions roasted whole with butter and herbs, yielding a soft, aromatic side dish.

Prep time
10 min
Time for cooking
70 min
Total process time
80 min
Created by Velvet Thyme Eleanor Hayes

Recipe category Everyday Cozy Plates

Skill level Easy

Cuisine type American

Yield amount 4 Number of servings

Dietary details Vegetarian-friendly, Free from gluten

List of ingredients

Main

01 4 large Vidalia onions, unpeeled

Seasoning & Aromatics

01 4 tablespoons unsalted butter
02 4 sprigs fresh thyme
03 4 cloves garlic, peeled
04 1 teaspoon kosher salt
05 ½ teaspoon freshly ground black pepper

Optional Garnish

01 2 tablespoons chopped fresh parsley

How to make it

Step 01

Preheat Oven: Set the oven temperature to 400°F.

Step 02

Prepare Onions: Trim the root ends and tops of each onion so they sit flat without removing the skins.

Step 03

Score Onions: Use a paring knife to cut a shallow X on top of each onion.

Step 04

Season Onions: Place each onion on a square of heavy-duty foil. Sprinkle with kosher salt and freshly ground black pepper.

Step 05

Add Butter, Thyme, and Garlic: Press 1 tablespoon butter, 1 sprig thyme, and 1 garlic clove into the cut top of each onion.

Step 06

Wrap in Foil: Wrap each onion securely in foil and arrange on a baking sheet.

Step 07

Roast Onions: Bake for 1 hour and 10 minutes until the onions are tender when pierced with a knife.

Step 08

Serve: Carefully unwrap, peel away skins, transfer onions to serving plates, spoon over melted butter from foil, and garnish with chopped parsley if desired.

Essential tools

  • Baking sheet
  • Heavy-duty aluminum foil
  • Paring knife
  • Oven

Allergy warnings

Be sure to carefully review every ingredient for allergens and seek expert advice as needed.
  • Contains dairy from butter; for dairy-free options, substitute vegan butter or olive oil.

Nutrition details per serving

Details here are meant for guidance. Please contact health professionals for medical advice.
  • Calorie count: 130
  • Fat content: 7 g
  • Carbohydrate: 19 g
  • Protein amount: 2 g