Start by bringing a large pot of salted water to a boil over high heat. Add spaghetti and cook according to package instructions until al dente, usually about 8-10 minutes. Drain the pasta, saving a little cooking water if needed. Toss the hot spaghetti with butter and grated Parmesan cheese until well-coated, then set aside, leaving it warm.

While the pasta cooks, chop the bacon into bite-sized pieces. In a large skillet over medium heat, add the bacon and fry until crispy, about 5-7 minutes. Remove the bacon from the skillet and transfer it to a plate lined with paper towels, leaving the rendered fat in the pan.

With the skillet still hot, dredge the chicken breasts in a mixture of flour, garlic powder, salt, and pepper. Cook over medium-high heat for about 5 minutes on each side until golden brown but not fully cooked. Remove the chicken and set aside.

In the same skillet, melt 2 tablespoons of butter over medium heat. Add the sliced mushrooms and Italian seasoning, stirring for about 5 minutes until they start to brown.

Add minced garlic to the skillet and cook for 30 seconds until fragrant. Pour in the Riesling, scraping the bottom to deglaze and pick up flavorful bits. Allow the wine to simmer and reduce by half, about 3-5 minutes.

Lower the heat and stir in the heavy cream. Return the chicken and bacon to the skillet, allowing everything to simmer for an additional 5-7 minutes, or until the chicken reaches an internal temperature of 165°F (75°C).

Taste and adjust seasoning with additional salt and pepper if necessary. Plate the buttery Parmesan spaghetti and spoon the Chicken Riesling over the top. Serve immediately.