Confit of Roasted Onions

Thin shavings of sweet onions and bunch onions cook down to a thick marmalade consistency when roasted in the oven with butter, olive oil, and herbs. The resulting confit makes a rustic farmhouse-style spread for sandwiches and burgers or a glaze for other vegetables or meats.
4 large sweet onions (about 4 pounds)
2 cups bunch onions (see note below)
1/4 cup butter
1/4 cup olive oil
1 teaspoon salt
1 teaspoon granulated sugar
4 fresh or dried bay leaves
2 tablespoons chopped fresh thyme leaves
2 to 3 tablespoons white wine vinegar

Preheat oven to 350 degrees. Slice away the root and stem end from the sweet onions, then cut into 1/4-inch thick slices. Trim away the roots from the bunch onions and slice, using all of the bulb and a portion of the green. Heat the butter and oil in a baking pan that is just large enough to hold the sliced onions in a layer about 1 inch deep. Add the onions and toss gently to thoroughly coat each piece. Sprinkle with the salt, sugar, bay leaves, and thyme, and toss again.

Bake in the oven, turning them often, until they are soft and a deep golden brown, about 45 minutes to 1 hour. Remove from the oven and let cool to room temperature.

Discard the bay leaves. Stir in the vinegar a little at a time, until the right level of "zip" is achieved. Pack the onions into dry, clean jars with lids. Store in the refrigerator. The onions will keep for up to 3 weeks.

Yields about 3 half-pints.

Note: Bunch onions are oversized green onions available in the early summer months, especially at farmer's markets.

Adapted from "The Glass Pantry," by Georgeanne Brennan