Preheat the oven to 375°F. Grease a 9x13” pan or two 9x9” pans with oil or cooking spray.

Boil elbow macaroni for 1-2 minutes less than the time indicated on the package (you want it to be not quite al dente, since it will continue to cook later in the oven).

Meanwhile, bring the squash, milk, beer, garlic, bay leaf, salt, and pepper to a boil in a large saucepan. Reduce the heat so that the mixture simmers and continue to cook for about 20 minutes, or until the squash is very tender. Do not worry if the mixture separates.

Remove from the heat and discard the bay leaf. Use an immersion blender to process the mixture until very smooth and creamy (or carefully transfer to a regular blender and puree in batches). Stir in the yogurt, gruyère, Pecorino Romano, and butter.

Add the elbow macaroni and stir until the pasta is evenly coated with sauce. The mixture will be very soupy. Season to taste with salt and pepper. Transfer the mixture to the baking dish or dishes.

Mix the panko and Parmesan in a small bowl, then sprinkle evenly over the macaroni.

Cover with foil and bake for 15 minutes. Remove the foil and bake for another 15 more minutes, until the top is browned and the sauce is thickened. Serve hot.