Classic Vegetable Stock Recipe

Place the dried mushrooms in a large bowl and pour 1 quart of boiling water over them. Set aside.

Heat the olive oil over high heat in a large stockpot. Add the chopped onions, celery, carrots, and fennel (if using) and stir to coat.

Sprinkle with salt. Cook over high heat for several minutes, stirring only occasionally. Cook until the vegetables begin to brown.

Add the garlic and tomato paste and stir to combine. Cook, stirring often, for 2 to 3 minutes, or until the tomato paste begins to turn a rusty color.

Add the mushrooms and their soaking water, the rosemary, thyme, onion skins (if using), peppercorns, bay leaves, parsley and 4 additional quarts of water.

Bring to a simmer and then drop the heat until you just get a bare simmer. The surface of the stock should just barely be bubbling. Cook for 1½ hours.

Using a spider skimmer or slotted spoon, remove all the big pieces of vegetables and mushrooms. Discard or compost.

Set up a large bowl or pot with a sieve set over it. Line the sieve with a paper towel or coffee filter and pour the stock through it.

To store, pour into glass jars and refrigerate for up to a week, or freeze. If you freeze in glass jars, leave at least an inch and a half of headroom so the stock can expand without breaking the glass of the jar.