Place a large pot of water on to boil. Add pasta and salt water. Cook to al dente.
While water comes to a boil, heat a deep skillet over medium heat. Add extra-virgin olive oil and butter. To warm oil and butter add crushed red pepper flakes, garlic and shallots, saute 3 minutes, add shiitake mushrooms and cook until tender, 3 to 4 minutes more. Deglaze the pan with sherry or Marsala wine, scatter in crabmeat - feeling for shell bits as you go. Warm the ingredients through, a minute or so, stir in tomatoes and heat through, 2 to 3 minutes. Stir in half-and-half or cream and reduce heat to lowest setting.
Drain pasta when cooked to al dente and toss with sauce and crab. Top with cheese, if using, and basil.
Recipe courtesy of Rachael Ray