Add the potatoes to a mixing bowl with 2 tablespoons of the olive oil, the salt, and the pepper. Toss gently to coat.
Transfer the potatoes to a baking sheet and roast for 20 minutes.
In the meantime, whisk together the remaining 4 tablespoons of olive oil with the parsley, garlic powder, and onion powder. Set aside.
Remove the potatoes from the oven. Use a pastry brush to coat the tops of each potato with the parsley and olive oil mixture. Use all of the mixture and distribute over the potatoes as evenly as possible.
Return the potatoes to the oven for 10 more minutes. Serve immediately with dipping sauce if preferred.
To slice the potatoes, place two wooden chopsticks - one of each side of the potato, and slice the potato in 1/4 inch slices. The chopsticks will prevent you from slicing all the way through. This will create an accordion affect during the baking process.