Makes 6-8 servings. Difficulty
3 pounds small red onions (about 9), halved through root end, then cut into 3/4-inch-wide wedges with some of core attached to each 1/2 stick butter, melted 4 garlic cloves, unpeeled 4 thyme sprigs 1 1/2 teaspoons coarse salt 1/2 teaspoon ground black pepper 4 tablespoons red wine vinegar
Preheat the oven to 450°F. Line a large baking sheet with foil; butter foil generously.
Place the onion wedges cut side down on baking sheet. Brush onions with melted butter. Add the thyme sprigs and whole garlic cloves to the baking sheet. Season with salt, and pepper. Drizzle the top of the onions, herbs and garlic with vinegar. Cover baking sheets tightly with foil. Roast onions 20 minutes. Remove the foil and turn the onions over. Continue to roast, uncovered until bottoms of onion wedges are brown, about 15-20 minutes longer. Remove foil. The onions are done when the bottoms of onions are brown and edges are slightly crisp.