Step 1

Heat the oven to broil. Bring a Dutch oven or large broiler-safe pot of salted water to a boil. Add the pasta and cook according to package instructions until al dente. Drain and set aside.

Step 2

Melt the butter in the same pot over medium heat. Transfer 1 tablespoon of the butter to a small bowl, add the panko, and stir to combine; set aside.

Step 3

Add the flour to the pot and whisk into the butter until completely combined. The mixture will look like wet sand. Cook, stirring constantly, until the mixture begins to dry out, about 2 minutes.

Step 4

Gradually whisk in a little bit of the milk until smooth, then whisk in the remaining milk and continue whisking until smooth. Bring to a boil, then reduce the heat to medium-low. Simmer, stirring occasionally, until thickened enough to coat the back of a spoon, 5 to 8 minutes. Add the cream cheese and stir until melted and smooth.

Step 5

Remove the pot from the heat and stir the Gouda, Gruyère, and 1/2 cup of the Parmesan in one handful at a time until melted and smooth. Stir in the garlic powder, salt, and pepper. Stir in the spinach and artichokes. Add the cooked pasta and stir gently until the spinach is wilted and the pasta and sauce are evenly combined.

Step 6

Sprinkle the reserved panko and remaining 1/2 cup of Parmesan evenly over the top. Broil until the cheese is melted and the panko is browned, 1 to 2 minutes.