In a large nonstick skillet, sauté pancetta over medium heat until golden, 3 minutes. Add onion and red pepper flakes; sauté until onion has softened, 3 minutes. Add garlic; sauté for 1 minute. Pour in wine; simmer until almost evaporated, 30 seconds. Add tomatoes with juice and tomato paste, squeezing tomatoes to break them up. Simmer, stirring frequently, until reduced and thickened, 10 minutes. Remove skillet from heat.
Bring a pot of water to a boil. Add salt and pasta. Stir and cook until al dente, 7 minutes or according to package directions. Reserve 1/2 cup cooking water; drain pasta.
Add cooking water, pasta and 1/4 cup pecorino to skillet. Cook over medium heat, stirring gently, until pasta is coated and sauce has reduced to desired consistency, 2 to 3 minutes. Top with remaining 1/4 cup pecorino and additional red pepper flakes, if desired.