Preheat oven to 210 degrees celsius (fan-forced).
Peel the kipfler potatoes and slice them down the middle.
Place the kipfler potatoes in a saucepan and cover with water. Bring to the boil for 10 minutes or until just tender (but not soft).
Drain the potatoes and place them back into the saucepan. Shake the saucepan over low heat to remove any excess liquid.
Meanwhile, place the butter and olive oil into a large baking tray and cook in the oven for 5 minutes or until hot and melted.
Place the potatoes into the baking tray and toss to coat with the oil/butter mixture.
Cook for 15-20 minutes.
Sprinkle with the lemon zest, paprika, salt and pepper and shake to coat.
Place back into the oven for a further 20 minutes or until golden and crispy.