Peel the sweet potatoes and cut them into small pieces
Boil or steam for about 15 minutes, or until soft enough to pierce with a fork
Drain and mash with a fork
Once cooled, transfer the mash into a freezer-friendly container and place in freezer until completely frozen
Place the frozen mash into your blending device of choice along with the yogurt/milk/cream of your choice (and sweetener if you wish)
Blend until it forms a thick ice-cream-like texture β you will probably have to mix it around a few times during this process to make sure itβs all evenly blended