Cook pasta according to package directions. Drain; keep warm.
Heat oil in a large nonstick skillet over medium-high heat. Add mushrooms to pan; sauté 6 minutes. Add Basic Marinara, red pepper, salt, and black pepper; bring to a simmer. Cook 5 minutes. Add shrimp; cook 3 minutes or until shrimp are done. Serve over pasta. Garnish with parsley sprigs, if desired.
Italian for "brother devil," fra diavolo sauce is usually tomato-based and always spicy. Although not traditionally included, mushrooms offer an earthiness that balances the sauce's heat. For a truly fiery dish, increase the crushed red pepper to 3/4 teaspoon.
I cut a corner on this, using some Ragu marinara I had in the fridge, so I can't comment on the sauce itself really though it was still really good. I also sprinkled some goat cheese on top like they do at one of my favorite restaurants. It adds some creaminess and cuts the spice a bit.