Peppery Portabellas with Pasta

Source: Mushroom Council

1 pound portabella mushrooms, without stems
12 ounces fettuccine pasta, uncooked
4 tablespoons olive oil, divided
1 teaspoon salt, divided
3/4 teaspoon ground black pepper
1 tablespoon minced garlic
1/4 teaspoon crushed red pepper
1 (15 ounce) can crushed tomatoes in pur