Place peeled sweet potatoes in cold salted water. Bring to boil and cook until fork tender. Remove potatoes from water and mash with a fork. Stir in warm cashew milk until creamy. Season with salt and pepper as desired.
Place kale leaves with fibrous stems removed into boiling water used for potatoes for about 10 seconds until bright green and tender. Remove from water and place in ice bath to stop cooking process. Place in food processor or vitamix and purée. Add a drop of water if needed. Slowly add in a drizzle or two of olive oil to emulsify. Add in salt as well as grated pamesan cheese if desired. Blend quickly to combine.
Top a scoop of potatoes with pesto and swirl swirl with fork or knife.