Preheat your oven to 400 degrees and line a small baking sheet with parchment paper. Place the cashews on the baking sheet and toast in the oven until golden brown, about 10 minutes. Set aside to cool.
Once the cashews are cooled, place them in a medium bowl and cover them with water. Cover them with plastic wrap and refrigerate for 8 hours.
Once the cashews have sat for 8 hours, drain the water and add them into a high powered blender. Add the coconut milk and a pinch of salt and blend until they form a smooth, creamy sauce. Depending on the strength of your blender, this could take some time, and you'll need to stop to scrape down the sides often.
Cover and refrigerate until ready to pour on ALL THE THINGS.
*If you want your sauce thinner, just add more milk! If you want the sauce less "nutty tasting" just omit toasting the nuts. You can also just use water if you don't want the mild coconut milk flavor.