The solution: A soak of 20 minutes in hot tap water was enough to soften the mushrooms, and 5 or 10 minutes more will do no harm. But perhaps more important than soaking is straining. Dried porcini are often packaged with foreign matter. Lifting the mushrooms from the soaking liquid with a fork helps keep the grit in the bowl. The leftover liquid should not be discarded but poured through a small mesh strainer lined with a single paper towel. This fragrant, brown liquid is used in the recipes that follow and can also be added to stock for mushroom soup or risotto.

HOW TO REHYDRATE DRIED PORCINI MUSHROOMS

Place 1 ounce dried porcini mushrooms in small bowl and cover with 1 cup hot water. Soak 20 minutes. Carefully lift mushrooms from liquid with fork and pick through to remove any foreign debris. Wash mushrooms under cold water if they feel gritty, then chop. Strain soaking liquid through sieve lined with paper towel. Reserve mushrooms and strained soaking liquid separately.

PORCINI MUSHROOM SAUCE WITH CREAM

Enough for 1 pound of pasta

Toss this intensely flavored sauce with one pound of dried (or one and one-quarter pound of fresh) fettuccine and one-half cup of Parmesan cheese. Pass extra cheese at the table.

3 tablespoons unsalted butter
1 medium onion, minced
2 ounces dried porcini mushrooms, rehydrated in 2 cups hot water, strained, and chopped coarse; soaking liquid reserved
Salt and ground black pepper
6 tablespoons heavy cream
3 tablespoons minced fresh parsley leaves

1. Heat butter in large sauté pan over medium heat. Add onion; sauté until edges begin to brown, about 7 minutes. Add porcini and salt and pepper to taste; sauté to release flavors, 1 to 2 minutes.

2. Increase heat to medium-high. Add soaking liquid; simmer briskly until liquid has reduced by half, about 10 minutes.

3. Stir in cream; simmer until sauce just starts to thicken, about 2 minutes. Stir in parsley, adjust seasonings, and serve.

TOMATO SAUCE WITH PORCINI MUSHROOMS

Enough for 1 pound of pasta

Toss this sauce with spaghetti or fusilli and serve with grated Parmesan cheese.

3 tablespoons olive oil
1 medium onion, minced
1 celery rib, minced
1 small carrot, peeled and minced
1 ounce dried porcini mushrooms, rehydrated, strained, and chopped coarse; soaking liquid reserved
1 teaspoon salt
1 can (28 ounces) plum tomatoes packed in juice, drained, seeded, and chopped
3 tablespoons minced fresh parsley leaves

1. Heat oil in large sauté pan over medium heat. Add onion, celery, and carrot; sauté until vegetables soften, 8 to 10 minutes. Add porcini and salt; sauté to release flavors, 1 to 2 minutes.

2. Increase heat to medium-high; add tomatoes and soaking liquid. Bring sauce to boil, lower heat, then simmer until sauce thickens, about 15 minutes. Stir in parsley, adjust seasonings, and serve.

TWO MUSHROOM SAUCE WITH ROSEMARY

Enough for 1 pound of pasta

Button mushrooms get a tremendous boost from a handful of dried porcini. Serve with orecchiette or small shells. So that the pasta better absorbs the sauce, simmer the cooked pasta and one-third cup of grated Parmesan cheese with the sauce for a minute or two, then serve.

2 tablespoons unsalted butter
1 tablespoon olive oil
1 medium onion, minced
2 medium garlic cloves, minced
1 teaspoon minced fresh rosemary leaves
1 pound white button mushrooms, stems trimmed and sliced thin
1 ounce dried porcini mushrooms, rehydrated, strained, and chopped coarse; soaking liquid reserved
Salt and ground black pepper
2 tablespoons minced fresh parsley leaves

1. Heat butter and oil over medium heat in large sauté pan. Add onion; sauté until translucent, about 5 minutes. Add garlic and rosemary; sauté until garlic is golden, about 1 minute.

2. Add button mushrooms; sauté until golden and liquid evaporates, about 8 minutes. Add chopped porcini; sauté to release flavors, 1 to 2 minutes. Season with salt and pepper to taste. Add soaking liquid; bring to simmer. Stir in parsley, adjust seasonings, and serve.