Preparation

• Position a rack in the center of the oven and heat the oven to 400°F.

  将牛肉骨骼布置在大型隔爆烤盘中的单层中。淋上2汤匙。油，然后用骨头擦油。烤，每20分钟转动骨头，直到深棕色，约1小时。

  Put the remaining 2 Tbs. oil and the onion, carrot, leek, celery, and mushrooms in an 8-quart stockpot. Cover and cook over low heat, stirring once or twice, until tender, about 15 minutes. Uncover, raise the heat to medium, and cook until the vegetables are browned in spots, about 3 minutes.

  Transfer the bones to the pot with the vegetables, leaving any rendered fat in the pan.

  Discard the fat from the pan, and set the pan over medium heat. Add the vermouth and bring to a boil, using a wooden spoon to scrape up any stuck-on bits from the bottom of the pan. Add the liquid to the bones and vegetables. Add about 1 gallon of water, and bring to a boil over medium-high heat. Add the tomatoes, thyme, parsley, and bay leaves. Reduce the heat to low and simmer gently, uncovered—the stock should barely bubble—for 6 hours, topping up the water level occasionally to keep the solids covered.

  Strain the stock through a fine sieve into a large bowl and cool to room temperature. Chill overnight; then skim off the layer of congealed fat.

Make Ahead Tips

The stock can be refrigerated for up to 2 days or frozen for up to 2 months.