3. Blanch the potato slices for 5 minutes. 1  Bring a pot of plain water to a boil. 2  Place your potato slices in a blanching basket (if you don't have a basket, you'll have to just drop the slices into the pot and remove with a slotted spoon). 3  Drop the basket of slices into the boiling water. Cut each potato into 4 pieces and place the pieces in a pot. 2  Add water to just cover the potatoes, and bring to a boil. 3  Cover the pot, reduce heat to low, and allow the potatoes to simmer until tender--approximately 20 minutes.