Place raw cashews in a bowl, cover with boiling water, and let soak for 15 minutes. Drain and rinse under cold water.
Add the soaked cashews, soy milk, tapioca flour, nutritional yeast, apple cider vinegar, miso paste, Dijon mustard, and salt to a blender. Blend on high speed until completely smooth.
Pour the blended mixture into a medium saucepan over medium-low heat. Cook, stirring constantly, for about 5 minutes or until the mixture thickens and becomes stretchy.
Remove from heat and stir for another 1–2 minutes off the heat to cool slightly. Transfer to a parchment-lined loaf pan, or shape by hand into a small log or block. Let cool slightly before serving warm, or freeze until firm for grating.
