In a large pot, bring salted water to a boil. Add the spaghetti and cook according to package instructions until al dente. Drain in a colander, reserving about ½ cup of the pasta water.
In a large pan or skillet, heat the olive oil over medium heat. Add the minced garlic and sauté until fragrant, about 1 minute.
Add the chopped sun-dried tomatoes and fresh spinach into the pan. Cook for 2-3 minutes, until the spinach is wilted.
Reduce the heat to low, then pour in the heavy cream and stir in the Italian seasoning. Allow it to simmer for 2-3 minutes, stirring occasionally.
Add the cooked spaghetti to the pan with the sauce. Toss well to combine, adding reserved pasta water as needed to reach your desired sauce consistency.
Stir in the grated Parmesan cheese, combining until the cheese melts and the sauce becomes creamy. Season with salt and pepper to taste.
Plate the spaghetti and sauce mixture and garnish with fresh basil leaves if desired.