Begin by bringing a large pot of salted water to a boil. Once boiling, add the penne pasta and cook according to package instructions until al dente. Reserve 1 cup of the pasta cooking liquid before draining the pasta in a colander.
In the same pot, melt 2 tablespoons of the unsalted butter over medium heat. Add the fresh spinach and sauté until wilted, about 2-3 minutes. If you're using frozen spinach, make sure to thaw and drain it thoroughly before adding it to the pot.
Add the remaining butter, cream cheese, sour cream, and parmesan cheese to the pot with the wilted spinach. Stir continuously until the cheeses melt and form a creamy sauce.
Gently fold in the quartered artichoke hearts and diced jalapeños (if using). Add the pressed garlic and mix until everything is well combined.
Add the drained penne pasta to the creamy spinach and artichoke sauce. Stir well to coat the pasta completely, adding reserved pasta water as needed to reach your desired consistency.
Once everything is mixed and heated through, serve your Spinach and Artichoke Pasta warm, garnished with additional parmesan cheese if desired.
