Once the potato is cool enough to handle, peel the skin off and dice into small cubes. Add it to a high speed blender (like a Vitamix, Blendtech or NutriBullet) along with the drained and rinsed cashews, 1/2 cup water, shallot, lime juice, lemon juice, nutritional yeast, cumin, garlic powder, and sea salt. Blend until smooth. Add more water as needed to thin and seasonings to taste.