Position a rack in the center of the oven and heat the oven to 450°F.
In a large roasting pan, toss the herb sprigs, carrots, celery, and onions with the oil, 2 tsp. salt, and a few grinds of black pepper. Spread into a snug single layer. Roast, stirring twice, until the vegetables are tender and browned in spots, about 40 minutes.
Transfer everything to a 6-quart heavy-duty pot, add 3 quarts cold water, and bring to a boil. Turn the heat down and simmer gently, uncovered, for 30 minutes.
Add the wine and simmer until the broth is reduced by about one-third and has a full vegetable flavor, 20 to 30 minutes more. Season to taste with more salt, if necessary.
Strain the broth through a fine-mesh sieve lined with damp cheesecloth or a coffee filter into a clean container, pressing gently on the vegetables to extract as much liquid as possible. Discard the solids.
If you are not using the broth immediately, let it cool, then cover and refrigerate or freeze.
Make Ahead Tips
The broth can be refrigerated for up to 3 days or frozen for up to 3 months.
nutrition information (per serving):
per 1 cup;
sat fat g
Photo: Scott Phillips