Bring a large pot of lightly salted water to a boil.
Meanwhile, remove any portabella stems by twisting off. Trim
and slice stems and caps; halve the portabella cap slices.
Begin boiling pasta according to package directions, usually
about 10 minutes. Meanwhile, in a large, nonstick skillet,
heat 2 tablespoons olive oil over high heat. Add mushroom
slices and cook, stirring, about 5 minutes. Sprinkle with
1/4-teaspoon salt and black pepper. Remove to plate; keep
warm.
In same skillet, add remaining 2 tablespoons olive oil.
Sauté garlic and crushed red pepper with remaining 3/4
teaspoon salt for 1 minute. Immediately add crushed tomatoes
and broth. Bring to a boil; reduce heat to medium and
simmer, uncovered, to blend the flavors and thicken the
sauce, about 5 minutes. Add asparagus. Cover and cook 2
minutes. Stir in cooked mushrooms and any accumulated
liquid. Use a spider to strain pasta into the sauce and heat
through. Serve with chopped parsley.
