Soak the cashews, either in cold water for 8-12 hours or in boiling water for about 30 minutes.
When ready, drain the cashews and add them to a blender.
Squeeze as much liquid out of the tofu as you can with your hands over the sink. Then break it up and add that to the blender as well.
Then add the non-dairy milk, the nutritional yeast, garlic powder, salt, pepper and agave to the blender.
Blend on high, scrapping down the sides as needed, until the sauce is completely smooth. It may take a few minutes. If you are having a hard time blending, add a splash more milk. Set aside.
Cook the macaroni according to package instructions. Drain and return it to the pot.
Pour the "cheese" sauce over the pasta and toss to combine. Taste and adjust seasonings. I usually add more salt and pepper.
Add the truffle oil and stir to combine. Serve.