This recipe calls for new potatoes, but you can use anything really, as long as it is a waxy type. The new potatoes have a sweetness and nutty quality that just really plays well with this iteration of pesto. If the potatoes are smaller- 1-inch or less- smashing them with a fork or cutting board is great. If they are bigger, slicing is a good way to go, or cut the potato into 1-inch chunks and go from there. This helps to keep a good potato to pesto ratio for good flavor. If you decide to salt the finish dish, be sure to use a large crunchy type and go light with it. This is one of those simple dishes where it is all about the ingredients, and how some things just seem to go so well together.