Cook the pasta according to package instructions until al dente. Drain and set aside, reserving 1/2 cup of the pasta water.
In a large skillet over medium heat, cook the chopped bacon until crispy, about 5-7 minutes. Remove the bacon and set aside, leaving the drippings in the skillet.
Add the diced onion to the skillet and sauté for about 3-4 minutes until translucent. Stir in the minced garlic and cook for an additional 1 minute until fragrant.
Pour in the diced tomatoes with their juices, and add the oregano, red pepper flakes (if using), salt, and pepper. Simmer for about 5 minutes to allow the flavors to meld.
Add the cooked pasta to the skillet along with the reserved pasta water and the cooked bacon. Toss everything together until well combined. If the pasta seems dry, add a little more pasta water.
Remove from heat and stir in the chopped basil and grated Parmesan cheese. Drizzle with olive oil before serving.
Serve immediately, garnished with additional Parmesan cheese and fresh basil if desired.