Heat the oven to 220 degrees celcius. Prick the potatoes with a fork, coat with cooking spray and place on a baking tray. Bake for 1 hour or until cooked.
When the potatoes are cooked, cut the tops off and scoop out the flesh, leaving a 1cm shell. Return the shells to the oven for 10 minutes.
Combine the ricotta with the potato flesh, garlic, chives and parsley and season to taste with salt and pepper. Fill each potato shell with the ricotta and herb mixture and return to the oven for 10 minutes. Top with the sweet chili sauce if desired.