Bring a large pot of salted water to a boil. Add the macaroni and cook according to the package directions until al dente. Before draining, reserve about 1 cup of pasta cooking water; you'll only add as much as needed to loosen the sauce. Drain the macaroni without rinsing.
While the pasta cooks, melt the vegan butter in a large saucepan over low heat.
Add the vegan cheddar a little at a time, stirring gently and allowing each addition to soften and melt before adding more.
Add the vegan cream cheese and stir over low heat until incorporated. If using the optional previously roasted garlic, stir in the mashed cloves at this point.
Pour in the unsweetened almond milk. Add the vegan Parmesan, garlic powder, onion powder, black pepper, and optional smoked paprika. Stir gently until the sauce is smooth and creamy. Keep the heat low and do not allow the sauce to boil.
Add the drained macaroni to the cheese sauce. Stir until the pasta is thoroughly coated, then cook over low heat for 1 to 2 minutes.
If the sauce is too thick, add reserved pasta water a small splash at a time until it reaches your preferred consistency. Remove the pan from the heat while the sauce is still slightly loose, since it will thicken as it sits.
Serve warm.
