Bring a large pot of water to a boil. Add the chopped squash and cook for about 5-10 minutes, until fork tender.
Using a slotted spoon, place the butternut squash in a large blender (leave the boiling water on the stove as you’ll add the pasta to it soon). Add 1/2 cup of the vegetable broth and blend until smooth. Set aside.
Add elbow pasta to the boiling water and cook for about 5-7 minutes. Drain, rinse, and pour the pasta into a 9×13 baking dish. Set aside.
Add the olive oil and flour to the pot over medium heat. Stir well to create a roux. Add the blended butternut squash to the pot and stir well. Bring to a boil and then turn the heat down to a simmer.
Add the remaining 1 cup of vegetable broth, cheddar cheese, 1/4 cup of the grated parmesan cheese, garlic powder, onion powder, salt and pepper to the pot. Stir constantly, until melted and smooth.
Pour the sauce over the pasta in the baking dish. Stir gently so that the pasta is evenly covered by the sauce (it may look like a lot of sauce for the pasta but it will cook down!)
In a small bowl, combine the breadcrumbs, remaining 1/4 cup parmesan cheese, salt, and pepper. Sprinkle on top of the pasta.
Bake in the preheated oven for 20-25 minutes, until the top is golden.