Boil pasta in salted water. Drain. While pasta is boiling...
Combine all ingredients EXCEPT Daiya in a medium saucepan and whisk. Simmer on medium heat and whisk ocassionally until the mixture begins to form large bubbles and thickens. Add the daiya and whisk until melted.
Pour the cheese sauce over the pasta and mix until well combined.
If desired, pour into a 9X13 glass casserole dish, top with breadcrumbs, and bake at 350 degrees for 25 minutes.