Preheat the oven to 400°F. Grease a 9- by 9-inch baking pan with butter.

Boil the pasta on the stovetop until tender. Reserve about ¼ cup of the pasta water and drain the rest. Rinse the pasta under cool water.

Stir together the milk and beer cheese in a saucepan over medium heat. Add a few tablespoons of the pasta water and stir until the sauce is slightly thick—it should not be runny, just thick enough to slowly drip off a spoon. Place the pasta in the greased pan and pour the cheese sauce over it, mixing well. Sprinkle the panko or chips on top, and then evenly distribute the grated gouda.

Cook for 20–25 minutes, or until the toppings are golden brown