Remove ribs from fridge 1 hour before starting your cook.
Preheat oven to 250°C fan forced.
Portion the racks from the bony side of the rack (see notes).
Generously salt and pepper the meaty side.
Place ribs upside down on a broiler pan with low sides. Make sure you keep space between the portions of ribs. You may need more than one pan (rotate the pans through the cook).
Roast for 15 minutes or until the bottom side of the ribs starts to crisp up and turn golden brown.
Remove the pan or pans from the oven and turn the ribs over and return to the oven. Swap oven shelves at this point if using more than one pan.
Roast for another 10-15 minutes until the ribs start to get crisp edges and are a dark golden brown.
Remove ribs from oven and baste both sides generously with the BBQ sauce of your choice.
Return ribs to the oven cook for another 5-7 minutes until the BBQ sauce gets glossy and starts to char. Remember to rotate the pans.
Get out your paper bags and leave them opened up on the kitchen bench.
Remove ribs from oven and baste them a final time with the BBQ sauce.
Using tongs, gently place ribs in the paper bags. Do not crowd them.
Leaving the bags expanded and full of air, tightly roll down the top of the bag a couple of times to seal in the ribs.
Let the ribs steam and rest for 10-15 minutes and then serve.