Place peeled potatoes in a sauce pan with cold water and bring to a simmer. Add a pinch or two of salt and cook until tender. Strain out water and cool potatoes on a plate in the refrigerator.
Heat oil for frying (350 degrees Fahrenheit). Thinly slice onion and toss in all-purpose flour. Fry until golden brown and crispy. Remove and let drain on paper towels. Fry potato peels until crispy and transfer to a pan lined with paper towels.
In a food processor coarse chop crisp onion and crispy peels. Place in a bowl and toss with cajun spice. This can be done days in advance.
When ready to serve, heat potatoes in lightly salted water. Melt butter in a saute pan. Add potatoes to saute pan and coat well with butter. One by one, coat the potatoes with the crust. Garnish with chives. Serve immediately.