Preheat oven to 375°F (190°C). Lightly grease an oven-safe skillet or baking dish and set aside.
In a large oven-safe pot or deep skillet over medium heat, add a small amount of oil or butter. Stir in garlic (if using) and cook for 30 seconds until fragrant.
Add uncooked ziti pasta and pour in broth or water according to your recipe measurements. Note: The liquid should just cover the pasta. Bring to a gentle simmer.
Reduce heat to medium-low and cook, stirring occasionally, for 8–10 minutes, until the pasta is just al dente and most of the liquid is absorbed.
Stir in cream cheese (or cream), shredded cheese, spinach, and chopped artichokes. Mix until the sauce is creamy and evenly combined.
Remove from heat. Taste and adjust seasoning with salt, pepper, and optional red pepper flakes.
Sprinkle additional shredded cheese evenly over the top.
Transfer the skillet to the oven (or pour into the prepared baking dish). Bake uncovered for 12–15 minutes, or until bubbly and lightly golden on top.
Remove from oven and let rest for 5 minutes before serving.