To make the bechamel you first make a light roux by browning the flour and butter in a sauce pan. It takes only a few minutes to reach a nice golden brown that helps enrich the flavor of the sauce.
Then toss in the onions and garlic and cook just until they have softened.
Next add in milk and allow to simmer of a few minutes.
The flour will cause the sauce to thicken. Add in cheese and spices and stir to combine.
Lastly add the cooked squash and stir until it is combined. cook the sauce just long enough to get it hot
Remove from heat and pour onto boiled pasta.
Spoon pasta into baking dish and sprinkle lightly with cheese and bread crumbs. Rather than bake an already cooked and hot pasta dish I like to just put it under the broiler for a few minutes.
Remove from Hot oven and enjoy!