I discovered fingerlings at a Farmer's Market a couple of years ago and found the best method that makes them fluffy on the inside and crispy on the outside. The parboil method may not be necessary, but otherwise it won't be so fluffy on the inside. Duck or goose fat is ideal for this, but I have never tried it due to cholesterol. Make sure to rough the potatoes up well in the colander to get a maximum crispness on the outside. I tend to eat them cold from the fridge the next day, but they can also be used as an appetizer with an Aioli dip or one of your choice. They are seriously addicting in our family!