Bring a large pot of salted water to boil. Add your pasta and cook according to the directions on the package. Drain and set aside.
In a large skillet over medium heat, cook your bacon until it begins to brown. Add the chopped leeks, onions, spinach, and butter. Season with salt and pepper. Cook, stirring, for a few minutes, until the spinach wilts and vegetables soften.
Add the white wine to the pan and cook for a few minutes, until the wine reduces by about half.
Add the cream and simmer the sauce for about 10 minutes.
Toss the pasta with the sauce and serve topped with the grated Parmesan.